Well, I finally got the boat out of the slip and on the trailer in the driveway. Put in the drain plug, filled up the baitwell and immediately found the leak. There is a 90 degree drain fitting out the bottom of the tank. The threaded coupler that clamps the fitting in place is missing. I assume it must have cracked and eventually broke off. The drain fitting has shifted and leak is between the fitting flange and the bottom of the baitwell. Relatively easy to find but more difficult to access. The baitwell drain is maybe 1 1/4" dia and connects to a short piece of hose, maybe 4"long, that tee's into a larger hose from the deck drain to the transom through hull. Access really is a mess. I'm not sure I can physically get to any of the hose fitting. I think most of this plumping was put in place before the deck was attached to the hull. So, a lot of the hose clamps are turned wrong for access through the tiny deck access and it all has to be done blind. I'm going to try to remove the baitwell recirc pump to gain room and disconnect the main drain hose at the deck drain to flex the main rain but I'm not confident.
Looking at options, I was thinking of prying the existing outlet up a bit into the baitwell and then putting some sealant underneath the flange. Maybe something like butyl RV roof tape. Its super sticky and I can work it into a gasket. I could then drill some small holes through the flange into the baitwell fiberglass and screw the flange in place with some stainless screws. Thoughts?