Re: 76 glastron ski-flite tri-hull floor replace
Holy smokes, a couple of locals on this thread! If and when you get you your resto, PM me and I'd be glad to share some info on distributors for materials (if you do decide to tackle yourself)! No fiberglass/composites retailers within 800km of Regina!
Like the others mentioned, if your floor is soft it usually means rotten stringers and possibly soft transom as well. I came to the same realization when I started tearing into my boat back in January. Actually, my floor was solid as a rock, but there were other tell tale signs.
Let me say this much, doing a complete resto, although maybe not in your immediate plans, can be a very rewarding experience. You'll learn a lot, and by the end know every square inch of your boat and know that it is in 100% ship shape. Doing a complete resto isn't for everyone, and will definitely cost some capital, but there is a HUGE amount of knowledge on this forum to help you get through.
Good luck and welcome aboard!