I just welded in a pair on my 65 street Dart, and forgot how important it is to support the front end in more than two positions to keep it from flexing when jacked and then winding up tweaked just a bit. As a result I have a very small paint chip on the left front fender where it meets the bottom of the body and the panels are tighter there than they were when painted.
I think we need to remember how old these car bodies are, and that support systems are even more important now than when new.