I'd check with a medium to high volume powder coating facility. They
have their share of dud runs, need to do this all the time.

I'd second the notion of using a standard auto refinishing system rather
than powder coat. My race car gang had their whole frame powder coated
over my mild objections. Between the runs due to poor drainage and their
inability to make up their collective minds on a few details like how to
mount the brake pedals, it never made it to the track in pristine
condition. And after the tech inspector had his say, there were a few
more brackets and welding that needed to be touched up.

Chris Wilson wrote:
I am re building a tube frame race car panelled in ali sheets that were
powder coated pre riveting. If I un-rivet the panels, many of which are
quite intricately formed, is there a safe way to remove powder coating
from fairly soft grade alloy sheet? I then want to re powder coat them,
probably in a different colour to the black which they are now. Most
have had some abrasion that has rubbed through the powder coating, some
have a bit of fretting around the odd rivet.

Thanks.