I made some tab's for the hatch out of G-10. Then used blind-nuts and decided to go with 2-56 x 3/8" flat-head screws that I'll counter sink slightly. It will have a clean look on the outside with the screws set in. When the plane is upright, you really can't even see the hatch. I CA'd all tabs in place and then put a bead of hysol around everything once it was all lined up. Definitely open to see how others solved this. I'm also open to suggestions. Rob