They don't move enough to be a concern, on the tires or on a jig. I've had cars that the door gaps looked goofy, jack up against the connectors, gaps look better, doors closed better, button it up. Works both ways.
This is another of those red herring deals. Like don't run a small port intake on a 340 or weak 741 pumpkins from bearing size. All bs...
Under 1/16th on the one we measured. With the tolerance these cars were built with, worrying about it is a non starter.
I guess it could be 'internet lore" as they say.
Not having a way to measure before and after of both methods, I know I was going with what seemed to make sense. I had the options of either having it supported on jackstands, or under the tires. Put a unibody car up on stands at one end, and the doors are tight.
And regarding the tolerances, my way of thinking is, whatever way they are stacked, I want to keep them as close to what they were when the car was welded together.
I don't doubt what you say about it not mattering where a car is supported. I just don't have a rotisserie (or the space for one) to try it that way. -I wish I did. I'd love to have one for my Duster project.
