: Hey Liz,
: Can you give us a run down on what they did?

: Bill

The builder I talked to had a recessed rim around the hatch opening, and spread "form-a-gasket (red stuff from Canadian Tire, henceforth known as FaG), around the rim after waxing the cover and rim edges. He then pressed the cover into the FaG material. He weighted it overnight, removed the cover and trimmed the cured FaG where it hung over the rim. This resulted in a gasket that perfectly fitted the hatch cover, so much so that he has to pry the cover loose for access. His hatches are now 100% watertight. He didn't have a finger divot, or any other type of help to open the hatch, and no "breather holes" in the bulkheads (although he might have by now, as we exchanged a lot of tips). He did get the deck cleaned up pretty well, but not well enough to satisfy him. There were still small traces of red gasket goop visible on the deck.
I can't find the PVA release agent recommended in the previous post, but did find some stuff on the web about using carnuba wax and hair spray, which I will try. Will post the results.