I'm converting a GP 25% Yak 54 from dual rudder servos to one pull pull servo. No one makes a 4" double arm with the correct offset, either of the aluminum cnc splined variety or the the aluminum type that bolts on to a servo wheel. Offset must be 7/16" -1/2" with crossed cables and location of rudder horns.

I was thinking to fab my own arm out of 1/8" 6061 aluminum and mount it to a plastic servo wheel that came with my 7955 servo using 4ea. 4-40 bolts but before I do I need to know; will the plastic splines hold up to very aggressive aerobatics?