I see the UMI upper a arms for a 72 gs have 1/2" and or .9 taller ball joints in them. if 1/2" is better than would the almost an inch be the best, or not so much? Also i see the arm it self is staight on .9 and bent on 1/2" balled arms. Whats with that? Thanx 4 any insite on this