When I finally removed the sheepskin seat covers on my '82 Spider I purchased 2 years ago to have the seats finally reupholstered, I found that the back plate / panel was missing on both seats. Not only that, but the interior rubber "bladder" that stretches and cliips to the frame across the interiors back to keep the foam from moving backward, also needs replacement. I have the seats at the upholsterer now and he's waiting on these parts to finish. Any suggestions besides dismantlers etc. (Which I'm searching). Anyone have experience with other options or manufacturing these parts themselves somehow? Appreciate any help or suggestions.