Bright Water has terrific Bomar Ocean Hatches, but the gaskets were over-due for replacement. Bomar sells the correct tubular gasket with a double-sided tape mounting system. Easy. Except for the removing-the-old-gasket-from-the-round-groove part.
Nancy’s side came out clean with just a little gentle and careful persuasion.
Shockingly, my side quickly turned into a complete disaster. Glue and torn gasket everywhere. It was hopeless.
I got out the power tools and sharpened the barrel of a 7in1 screwdriver using a countersink bit.
I then chucked the whole thing in the drill and used it to clear the groove. It made a mess of the mess, but worked well.
Installing the gasket was easy. Good as new.