Are you hitting the UCA when you are turning the wheel with the car on jackstands or not at final ride height? When the suspension is full drooped down it will get closer to the UCA.
You can actually see the rim hitting the UCA, right?
Sometimes there is a nub on the LBJ that hits the LCA to limit the turning before the box itself hit it's locked point. I could imagine hit point on the LBJ wearing over time and/or the nub on the aftermarket LBJ varying.... Anyway, it's doesn't matter much. You just don't want the rim to hit the UCA at full lock.