RE: Fuel proofing inside of fuselage.
Thanks for all of the ideas, I am going with a combination of epoxy on the engine side of the firewall, and spray the fuel tank bay with Rustoleum clear polyurethane. Tailskid, I hope you are right about this, I know the first part of your answer is true. If you DON'T fuel proof the tank area, it is SURE to leak. Already been there and done that.
Thanks again from old bird.