The foam will certainly stay. Hindsight 20/20, I probably should have made my extension to match a standard length long-bed. :P I'm not so sure anyone will want plugs in the dimensions I used, although I suppose they could be cut down to length for other projects.
I agree about it being best to lay it up on the bias, but it seems like it's going to add a lot of complexity... I can lay three widths of the fabric side to side across the top and cover the entire thing, or I can make a dozen cuts and piece the surface together on the bias.
(@ AndrzejM) I do expect to do two layers on the outside surface of the shell.
I might go ahead and start with the simple, non-bias layup and then go back and do the second layer on the bias. Two layers should give me a much more solid surface for filling and painting... All of my corners are a bit rounded to make it easy to contour the fabric around.
I've seen these hinges used on commercial camper shells where the're a long rail with a sort of "C" groove at the end. The door has a matching rail that fits into the C groove and rotate within it as the door lifts up. Do you guys happen to know what those are called?
*wanders off into the garage...*
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