If you have a blue metal arm that is included in many Hitec servos, it will work perfectly. See my webpage for a good how to about that. Same with removing the "tang" of the throttle return spring. I just snip the U bent part that hooks over the shaft plate. You want to leave the SPRING in place, because it acts as a spacer for the shaft/body, and keeps the butterfly from wobbling/wearing in the venturi.