[paulk]

We had a similar problem (bigger)and fixed it by fiberglassing end-grain balsa to replace the rotted material, since that was how it was originaly built. We had to cut or grind out the inner headliner to remove the rotted material; it sounds like your access doesn''t require such drastic measures. I would be concerned about a possible weakness in the deck where the plywood sheet butts up against the original material, unless the piece you''re replacing is one of several layers. We were also careful to use fiberglass resin so as to maintan the same flex and bonding characteristics as the original material. Using epoxy might create a "hard" spot that could lead to problems later. Happy gooping!