Tire wear, what's causing this! ? ?

In response to post 115; The early arms have the pins pointing up to the hood. The later arms (73up) have the pins pointing down.As mentioned earlier; the arms and centerlink are treated as a set between year groups. ie, the early arms go with the early C-link; the late with late.
I think it was post25 that showed the LATE (73up)pin orientation..
Post 60 shows the early pin orientation.