Steering joint replacement

[cptspaulding]

Comparing the two, the new one is painted black (which could be adding to the problem)

Speaking from experience, that is indeed your problem. You'll need to take a wire brush to the splines & get the paint off. My mechanic flat out refused to fit it as it basically didn't fit. Ended up taking the paint off & doing it myself. Two years later there was so much play on that knuckle it was scary so I replaced again with a genuine Mr T unit.