: Both times, I had a section of hatch where the taping and bracing to keep it
: in place failed, and of course, the lip lay up suffered as a result. That,
: I can remedy by just shoring it up more. But, the most distressing problem
: is that in both attempts, I can't seem to find the trick to getting the
: glass to lay up close and tight to the mold for the weatherstrip channel.
: After the glass dries, I take a look at it and it's messy, has ragged
: edges around the mold, it's got gaps between the flat section that the
: hatch will rest on and the sides of the weatherstrip channel, and it's
: just plain ugly.

Don't make a weather-strip channel. Just make the lip a flat surface without trying to make a channel for the weather-stripping. You do want the lip recessed enough that when the hatch sits up on the weather-stripping that the top of the hatch cover is flush with the deck. To do this push the hatch cover so it is recessed from the outer deck surface by about 1/8".

Recessing the weather-stripping does not improve the watertightness of the hatch and if it is hard to do, don't bother.