Body panel replacement

I’d like to add my thanks to the responses to this post. I’m at the point of replacing the full quarters on both sides of my 65 Dart coupe. Yesterday I finally got the trunk surround, including the lower rear window frame, from my donor car welded on. I was thinking of putting it on my rotisserie to do the quarters, but wasn’t sure if I should. Now I definitely will wait until I have the quarters on. After replacing the floor pans I welded a cross brace across to each door jamb with a triangular “V” attached to the top of the driveshaft hump. I also used braces from the hinge mounts to the latch to keep things square that way. So far, so good. When I replaced a section of the driver’s side rear sub-frame I made jigs that ran between each spring perch, making sure that the center-to-center distance matched the specs on my factory frame chart. Interestingly enough, the passenger’s side perch was 3/16” short from the factory. Thanks again for the informative responses. I’m not a body guy, so I’m always glad for any help I can get.