Needing to make about an 8 x 8" end cap with flanges of about 1/2" with 0.027 aluminum coil stock. Some of the corners are right angles so I can just notch the corners but would like to have a bit of cover over the mating part so thought I would leave 1/8 -1/4 that will need to form a compound curve - needs to compress and some minor wrinkling is ok. Notching the corners most of the way will hopefully minimize this issue. Some of the edges are curves so some stretching/compression will happen.

Also going to make a die to punch out the shape with flanges from flat sheet. That seems pretty straightforward.

For the forming operation I am thinking about how to hold the part. If I put the pocket in the lower die I can cut the outline of the part in the top of it for initial placement. But when the upper form comes down he part may shift. Seems like I need to clamp the center portion somehow. I have some ideas about this but all are fairly complex. Any suggestions on this?

Two of the edges are straight and parallel so I suppose I could do those edges first and then clamp them somehow to do the other edges but the corners where some compression will happen in the flanges is an issue. Looking for ideas/suggestions...