He did say ball joint nut (not ball joint) in the post#1
and to barracudadave67 sorry I missed the wording.
There are no threads in the UCA where the ball joint screws in,
I guess I take it that most people know that and if the hole is to big to hold the ball joint I would look for another arm, I know there were a few that had a small weld from the factory at some point in the 70's but I have only seen a couple. I have changed many upper ball joints and never had one that wouldn't tighten up. I never tell anyone to weld on a steering component because you don't now what experience they have or don't have. You don't know what he means when he says the ball joint wont tighten up, the hole might be way to big and a spot weld might hold it for a while then in a hard corner work the weld till it rips out the small piece of the sheet metal control arm and the ball joint pops out leaving you with no control of your vehicle.