Our Zia is desperately trying to become the most spoiled vessel on this forum. Being horrible 'enablers', we promptly replaced her existing portlights with brand new New Found Metals (NFM) stainless steel and tempered glass portals. This made her very happy and closer to her goal. All 4 portlights on starboard side. After installation of the smaller 4"x14" Portlight This is the 'Before' picture, complete with Silicone Caulk 'improvements' done by a previous owner. The following is more detail than most folks would want unless they are considering a similar upgrade. I'm going to include my step-by-step directions and some Tips that I would have appreciated knowing when I started. But first, here is some basic anatomy: The Spigot is pushed through from the inside, and it screws into the Ring (which comes from the outside) to hold the assembly into place. The majority of the Portlight including the glass window, is attached to the Spigot. Here is a side view (cross section): draw up a better view of spigot, ring, drains and insert here! NFM has a useful You Tube video showing a basic install, but it doesn't have a lot of detail. It's been quite messy, a lot of work, and several marine-grade curse words were dropped. But I have to say it's been one of the most satisfying upgrades we have done. The portlights are excellent quality (IMHO), and they seem much more rugged than our originals. We (6 years ago) had replaced the plastic lenses on the existing ports because we couldn't see through them and they were already getting clouded again. The new ones, being tempered glass, should be much better. Seeing out of windows is a nice thing! Our old portlights were seeping water and a previous owner had done a horrible fix using Silicone Caulk. I don't hate very many things, but I really hate Silicone Caulk in the hands of DIY boat owners. This has been on our capital expense 'wish list' for a while. I recently called NFM with a question for planning purposes and talked with Richard the owner. He was lamenting about the looming tariffs (40%) because the factory is in China. That pushed me over the edge & we ordered replacement portlights. I guess that means I was looking for a reason to upgrade sooner rather than later. Great sales tactic, Richard! ;-) We ordered replacements for all 8 portlights: 4" X 14" normal stainless portlights with 1.5" spigots (4 each) 4" X 14" stainless portlights with 2" spigots (2 each) for the head and the quarter berth since these wall thicknesses are larger. 6" X 26" stainless portlights with 1.5" spigots (2 each) for the Nav station and the Galley. 6" X 26" Teak Spacers (2 each). The wall thickness on these two big ports is small enough that the teak spacers are desirable. While NFM has a nice video showing a basic install, there weren't any step-by-step instructions. So here are my notes on basic step-by-step installation: Remove existing portlight. Phillips head screws, chisels and scrapers to pry old windows out. Clean up any mounting material that would interfere with clamping the template on the outside wall. Clamp NFM template into place (on the outside). Be sure the drain semi-circles are on the bottom. Measure top of template to corner on cabin top to ensure portlight is aligned with cabin top. Drill 3/8" holes for bolt holes using holes in the template. Place dowels into bolt holes to ensure alignment. Use a sharpie to trace the inside lines of the template. Use a Compact Router or Laminate Trimmer with a flush cut bit to cut out the curved areas where the drains are located. Remove the template and use a jig saw with special fiberglass blade (see Tip #7 below) to cut the rest of the opening. Cut slightly outside of your drawn lines because you can fill it in with Butyl for a better seal. Use the counter sink bit (order the counter sink bit from NFM) to bore out about 3/8" deep for the ring bolt studs (aka the thing you screw the bolts into). Use a 45 degree angle bit on a Compact Router or Laminate Trimmer to create a bevelled edge to all the inside and outside edges, and the outside bolt holes. This makes it much easier for the Butyl to get shoved into the gaps, both inside and outside. Dry fit the ring into the outside holes. Be sure the ring bolt holders fit totally in the holes and the ring therefore fits flush against the outside. Dry fit the spigot/portlight from the inside. Clamp it loosely into place so you can go outside and be sure there is at least a 1/4" gap between the spigot and the cabin walls. Remove hardware. Do intense cleaning using razor scraper and sandpaper. Remove any traces of Silicone Caulk or other packing agents. Vacuum and clean all surfaces. Use Acetone on a rag (and rubber gloves) to clean the dust off the surfaces and bolt holes. Use rag on a screw driver in the bolt holes. Acetone clean the ring and the spigot surfaces that will be receiving Butyl. Pack Butyl on the spigot - the width should be roughly the cabin wall thickness and have it tapered out to nothing on the outside of the spigot. The NFM video is useful for visualizing this. If you are using a teak spacer (like on the Nav station and Galley large portlights), be sure to put the teak spacer on the spigot before you put the Butyl on the spigot. Use closed cell foam tape (from NFM) to line the outside of the ring. Roll and pull on a Butyl strip to thin it out to about 3/8" cylinder and apply this to the inside of the ring. The NFM video is useful for visualizing this. We also pulled very thin strips of Butyl to wrap around the bolt structures in the ring. Carefully push the spigot into the hole in the cabin side (from the inside). When you're sure you have it lined up correctly, use clamps to push it into place, and flush with the inside cabin wall. You will need to put a block on the outside of the ring to ensure you are not clamping the spigot. Go to the outside and there will be gaps between the cabin walls and the spigot. These are important to fill so that the Butyl is standing a little bit higher than the cabin wall. The NFM video is useful for visualizing this. On the outside, place the ring. Use clamps (and blocks - see Tip #8 below) to get it set in place and tighten them enough that you can start threading your bolts. Thread the bolts incrementally going around the spigot and gradually tightening them into place. As you gradually do this, the Butyl will be compressed and should ooze out of the gap between the spigot and the ring. This is where you should know the difference in feeling between the bolt 'bottoming out' and the bolt gradually clamping down on the Butyl. (see Tip #5 below) Wait a day to let the Butyl ooze. Go have a cocktail to celebrate your new portals. Then remove each bolt one by one and squirt the bolt hole about half way full of silicone caulk. Squirt it as far back as possible so that it is against the ring. Then tighten the bolts down again. This is the only legal use of silicone caulk on your boat. All other uses are highly illegal and in bad form. Go outside and you should see the foam strip on the outside of the ring very compressed against the cabin wall. Compressed to the point that maybe 1/16" or less of foam is visible. If the screw is fully tightened and there is too much of the foam strip showing, your screw is probably 'bottomed out' and you probably need to cut off some of the fastener (see Tip #5 below). Clean Up. Use a razor/box cutter to cut the Butyl which as oozed outside of the ring. Use a tiny amount of Acetone to clean up cabin wall. Tips (in no particular order) Have a good shop vacuum handy. Use it often on the inside and outside of the boat. We covered the inside of the boat with plastic drop cloths taped to the cabin walls below the portlight. We used residue free duct tape (don't use regular duct tape!). It was still messy but the plastic sheeting helped. Protect your Butyl. Don't let dust/cuttings settle on your Butyl - cover it with plastic. I lost a couple rolls because dust/cuttings settled on it. Be sure to water test your portlights after they are installed. At first we didn't test them and I happened to stop by during a rainstorm and there was significant leaking on a couple of portlights because the bolts had bottomed out in the ring. (see next tip) There is only roughly a 1/4" of bolt thread going into the ring. On 3 of my portlights, the bolts bottomed out in the ring before they had enough tension. So I needed to pull each bolt out and cut off 1/4" and tighten them back down. I don't know if it was my measurements of the cabin wall thickness being slightly off, or if NFM sent me longer than needed. I used my Dremel tool with 1-1/2" EZ lock Metal Cutting Wheels to cut the bolts. So before you get started, try tightening a bolt down into the ring so you know what it feels like when it 'bottoms out' in the ring. During the installs, if you 'bottom out', cut about 1/4" off the bolt end so you can be sure to apply enough tension 6. Loosen and remove shrouds when they are less than 8" away from the portlights. This is far easier than trying to battle your way around the shrouds with jig saw or router. Before you slack the turnbuckles measure the lengths or count the threads (and write them down), so you can correctly re-apply tension when you are done 7. Get a special Bosch TM341HM1 jig saw blade (actually get several of them!) for cutting fiberglass. It is a huge improvement when cutting fiberglass over normal metal or wood blades. In fact, it's almost impossible with normal blades. 8. Have some wood blocks (approximately 1"x1"x1") that you can use when clamping the ring and spigot together. The blocks can be seated on the ring to prevent the clamps from being seated on the spigot. I would have about 4-5 of these blocks ready. 9. Beware of the tension on some of the portlight dogs (latches). After we installed the big portlight over the nav station we were disappointed that it leaked when we sprayed the outside with water. We were horrified by the idea of needing to yank the whole thing out and start over. It turns out the dogs were just too loose and there was not enough pressure between the hatch and the gasket. It felt quite loose and we used the little Allen wrench tool that came with the portlights to tighten things up. Then it held water fine. 10. Butyl is your friend. The professional boat repair/fitting folks always use butyl for bedding hardware on the deck/cabin. For good reason: it oozes and seals very well. It was fairly cool (50 degrees F) when we did our install and our black butyl from New Found Metals (NFM) was quite clean and easy to work with. If it is warm or hot it can be quite a mess. Our experience? We would for sure do it again, and it was well worth the time and expense. And what was the time and expense? All of this cost about 3.5 boat bucks, and I'd guess we spent a total of 60 hours working on the installation and cleanup. We were taking our time and trying to do it right. These are really nice portlights. It was a fun project for my wife (Susan) and I and I'll be revising this description as I think of content we have missed.