I'm attaching the panels using these trick tabs and a spacer to set the depth.
I really like these u-nuts. They float in the hole which allows for extra misalignment
Here is a panel all wrapped up. I like the material but I need to redo this one. I didn't realize my clamps were digging into it and I had missed some spots with adhesive were I was holding the panel while i was spraying. my only regret is putting a hard break in the panel instead of bending it with a radius. oh well