After cutting some ragged looking bows for the hatch...and not being very pleased with my efforts, I decided to trash the plywood bows.
I can work steel better than I can wood....so why not ?
I built a hatch frame using thinwall 1" square tubing and 1" angles.
Much better ! After 1/4' plywood and aluminum skin...just 31 lbs., ..so I am pleased all the way around..
May be worth a try..
BTW...took my tear down to scales for weighing for registration...780 lbs, still not too bad..
Hammer & Tongs