I have heard the same about the threads coming out when replacing ball joints. My 74 still got factory pieces and I'm affraid when times come.

In Vzla is not uncommon to find weld points ( 2 or 3 ) to keep ball joint and UCA safely in place. Not just on 73 and lates B bodies, but on any Mopar. Need to note, Venezuelan cars are tipically abused.

On my LCA ( press kind ) i had to make a weld seam on the new ball joint to make it larger diameter and make it fit tight again into the LCA hole. They were moog problem solver ball joints ( which I think are around .002 larger ) and still fit loose.

NOS LCA are anyway ready to get in to my car soon, with ball joins and bushing already installed from factory.

About the rest parts of suspension... nothing worst or better than any other Mopar.