Bruce,
I wasn't as careful as I should have been in enlarging the openings for the main cabin windows. The new windows are a little larger than the original openings. I used a rotary tool that I wasn't used to and that was too hard to control. I've since bought a good jigsaw with excellent quality blades that makes my life so much easier. I've used that for cutting out all my bulkheads and panels since then and what a difference quality makes. The Dremmel Trio, the rotary tool that I used, has its place such as cutting holes to large for a drill or wood strips when using its edge guide.
The other issue I ran into, mostly because of having a wider gap between the window frame and the fiberglass than I needed, was using too thick a layer of sealant on the outside and it bent the window frame a bit at the bolts when I tightened them. I was able to correct the issue, but it took a lot of extra work.
I also found that the finish bolts that Steve provides were difficult for me to use, but probably because I was doing most of the work by myself. The nuts are inset into the backing plate and give a nice finished look, however, to use them the holes through the fiberglass and the backing plate have to be perfectly straight. Mine weren't and after several attempts to use them failed, I bought new SS bolts with SS nylon inset locking nuts. It still looks nice on the inside, but not as finished as Steve's nuts would have looked. If you have several people to help hold the backing plate in place and you're careful in drilling each hole, you should be fine.
The one thing I did learn is the Butyl sealant that Steve includes is fantastic stuff to work with and I now use it wherever I can. It's easy to work with, doesn't harden and doesn't leak. It's the same stuff most windshields are installed with and easy to find at any RV store or auto glass store.
There are a few pictures of the windows as I installed them on my website under the v-berth and main cabin sections. I hope this helps and don't hesitate to ask if you have any questions. I'm about 20 months into the rebuild project now and I'm not the same person I was starting out. The stuff that I've learned and the things I'm able to do now blows my mind. As they say, practice makes perfect.
Ric
s/v Blue Max
#2692
www.ric-maxfield.net