Windshield Glass, by Jimmy Watts
I have had right much expereince with the glass problem that you asked about. I build new replacement frames for Hatteras boats and such. There are a few steps that you need to make sure that you do to prevent leaks in the near future.
I use the 1/4" laminated safety glass, (unless the owner requests tempered), the tint is most likely the green tint, make sure the edges are sanded extra good (caulking sticks to rough surface better), try an get about 1/4" gap around the edges of the glass next to the frame. Before you remove the old glass, you might get a piece of card board the will cover the window and make a pattern. This way you can leave the old glass in tact until you get the new one.
Once you remove the old glass, remove as much of the old caulking as possible. If you don't, it leak for sure. Install the neoprene gasket materail, install the butyl (if you want), place the new glass in position. If you put butyl in, make sure glass in in correct position before you set it down because it gets very hard to move once it makes contact with butyl.
With glass in place, get 1" tape and tape off the upper or outer groove in the extrusion. You need to keep any caulking out of this groove or else getting the vinyl in will be really hard. I use the Sika caulking (black messy stuff). Cleans up good with denatured alcohol. Once cauling is in, smear around pushing downward forcing it into cracks and voids. If you put the tape on in one long piece with a tail to grab to start removing it with then remove the tape and insert several retainer strips. I always wear latex throw away gloves doing the caulking. Make sure you have trash bag near by.
Let dry for about 24 hours, remove any major excess amounts with razor blade, install vinyl, squirk more caulking under vinyl, use flat object and flatten vinyl causing excess caulking to squeeze out. Let dry for 24 to 48 hours, razor blade cuts excess caulking off and then hire someone to clean the windows. Hope this helps, if you have any questions, I will be happy to answer them if I can. My number is 252-634-2214. Thanks
Jimmy Watts
ps I forgot about the silicone. It has a tendency to pull away for the glass and if this happens of course, resealing will be necessary. Once you have used silicone on the frame, I can not find a way to remove the residue 100%. It leave an oily, greasy feeling film that will not allow the Sika to adhere to. Other caulking might stick to it, I am not sure.
A friend of mine with an 37 has had a night mare with his windows because someone installed his glass with silicone. We have now put in new frames and now no more leaks. This is some of the experience that I can tell you about first hand.