These boats were not meant to be taken apart and it was assumed they would never leak. Ha! Which fittings exactly are you having a problem with? Handrails? On the 37 they are through-bolted to interior hand rails. Offhand, I can't think of anything else that actually goes through the headliner that I did not myself install. I cut big plugs for those items (vents) and found that the deck and headliner are the pieces of bread in a balsa wood sandwich. In other words, there is not a separate head liner. ('82 vintage boat). Uou might try using BoatLife liquid sealant if you know the origin of the leaks.