Got to work on the rear section, scraped off 10 lbs. of old sound deadner tar and roughly pounded out the dents and kinks. Then braced and squared it up, not easy, it was like trying to square up a sheet of tinfoil, took a lot of material.
Then trimmed and fitted one of the remaining rear door sections and tacked it in. I used a piece from the old rear part of a front door to splice into the top of the quarter panel to eliminate the old C pillar. I'll use a piece of the original mid post to make the new door post at the front of this quarter panel.
Actually so far, I'm finding it's not so much fabrication as repositioning of all the pieces.