While we're on the subject of the door posts, I had originally intended to just leave them where they were welded and clean up the existing crappy welds. After all, the car had been assembled with the doors hung. After I started comparing the door post locations with the assembly manual, all that had to be rethunk.
Turns out that the original builder couldn't read a ruler any better than he could weld. Even though the locations of the parts are clearly described, he managed to get them way off and then proceeded to weld them there. Oh well, that shouldn't surprise me at all. He also managed to get the rear body section mounted too far forward, which explains why I was having such a hard time getting the doors adjusted. I cut the posts loose and repositioned them where they actually are supposed to be.
https://i.imgur.com/9v8mkTy.jpg
https://i.imgur.com/43bpyKi.jpg
I think these are the last of the builders "welds" that I have to fix.