Woody wrote:I think I understand the principle of what you are saying, Does hinge attach to the hatch from underneath via the studs?
Yes!
Woody wrote: I used a flat piano hinge and covered over the top with flat rubber material wider than the hinge and pinned down the sides with flat bar aluminum that is screwed down to hold them in place
That would work too. The main difference is you see your screws, my way they would be hidden!

Mike...