Thanks again Paul. I used that block and screw idea to attach the deck. It works great.

The latest news is that both hatch braces that I was having trouble with fell off. They had perfect imprints of the hatch's wood grain but did not bond. I'm using MAS slow cure so blush is probably not the culprit. I suspect it was the lack of sanding even though the surface is anything but smooth. The third brace is well attached (I hit it with a hammer side ways trying to jar it loose) so I'm going to leave it alone. I'll sand the attach areas with 80 grit and try again. I think I'll use the wife's idea to precurve the hatch with strap clamps and then lightly - DUCT TAPE - the braces in place. I may have starved the joint last time by clamping them too tight. I'm just not going to take any chances.

John