Off Topic: How to glue to the interior of a lined fiberglass top

Scuff the finish off carefully with a grinding disc on a drill or air grinder. Use a product called Sticky *** Glue (Amazon-4 oz size is fine.) This is a PERMANENT situation, so be sure of yourself! Since you can't clamp it, I suggest using a couple stainless wood screws from the outside and seal over them with urethane. This glue is thin going on, but it's a PE glue and will expand-that's why you need to clamp it or screw it down. Trust me-you can glue two pieces of wood together, clamp it, and 30 minutes later, the bond is actually stronger than the wood! Good luck!