1937 Dodge Coupe Roll Pan

[hemiyota]

This thing has been giving me a fit! I've probably made about 15 or so of these. I have nothing there to make a FSP with. I made a pattern of the bottom of the deck lid, cut a blank, wheeled a little shape into the piece and then tipped the flanges. The top of the pan will match the deck lid when I hold up on it, but when I let the panel go down to match the sides, the gap goes all wrong. It looks like this would be a fairly simple piece to make, but I guess not. Has anyone ever made one of these, or can anyone tell me what I'm doing wrong......