Took out some plywood to recarpet it. Its in a fish and ski type boat. There is a livewell / baitwell in the area I'm recarpeting. On top of the livewell between it and the plywood was some type of putty (plumbers putty?) or caulk. Was still soft enough to scrape off. Not sure what to use to seal around it with. Anyone have an idea of what to use? TIA