QA1 Aftermarket K-member Problems?

are you saying that you've found differences between different pitman or idler arms from the same 73-76 "generation"?

Yes. Not all pitman and idlers are created equal, even within the 73-76 range. Some of the brands out there have slightly different styles, and then of course there’s quality control. I know that on one particular moog pitman arm I installed the pitman slid further up onto the splines than then previous one did, to the point that the pitman nut bottomed out before the pitman arm was secured. And no, that wasn’t a small sector/large sector mismatch, it was a large sector box.

You swapped the parts over from the stock K, but do you know if they’re stock, or aftermarket, or even the same brand?