Thanks spears, I expect to nibble down the length. I am deeply concerned that I will get severe warpage. Perhaps it would be prudent to get the sheet metal brake fabricobbled first, and pre - bend the profile , then use the dies to finish the shape?

This weekend my spare time generated greenbacks rather than progress. I lifted the box off a delivery truck, then changed all the mounting tabs to fit another. The lifting was sketchy, nearly dropped if off at the end. Got over confident, but all's well that ends well. Hopefully back on the Plymouth this weekend.