Mike,
Use H-9 aluminum arms on the servo with Rocket City 4-40 ball link screwed into them. Put a nut behind the bolt to give double safe attachment. Do the same on the other end where it attaches to the stab. The nylon ball links wont allow any rotation on the pushrod, you might even place a jam nut just for the comfort level. My Su-31 is dead tight - absolutely no wiggle at all.

Tom