Yes, I know that the shims are for caster and that they have nothing to do with ride height. It was just during the trying to figure out why the truck sat unevenly that the shims came into the discussion. The truck sits fine now. My main question, really, is if the caster shims are too thick to allow the u-bolt pins to go into their holes, should I go to thinner shims? The truck seems to be fine with the shims that are there now. If I get the pins in the holes on both sides, doesn't this automatically mean that the axle is positioned correctly under the truck? The whole thread about uneven ride height is here: https://www.stovebolt.com/ubbthreads/ubbthreads.php/topics/1270094/1.html

1956 Chevy 3200