Attaching galley aluminum?

I know this has been addressed before, but I could not find where it is. I am wondering how others have attached the aluminum skin to the galley hatch. I have the inner galley skinned with 1/8" birch plywood. I plan on floating the skin on the TD camper top and covering the ends with end molding and screws. I can't do that with the galley as the 1/8" plywood and aluminum will be hanging over and covering the 1/2" sides. This is my last step, please offer some experienced advice. Thanks in advance!