I am about to begin tearing out the soft spots in the deck of my thunderbird seminole trihull (17' outboard). It is about a 69 or 70 model. I will tear out the entire deck if there is excessive deterioration. I will inspect all the stringers and the transom. I have two questions. When I core drill the transom from the inside for rot detection, how should I fill the holes providing the transom is okay? Next would it be okay structurally to install an access hatch in the deck for storage? There is no opening in the deck now. Any advice would be appreciated.
