Glad to see this post Neil, of the 2 I just rebuilt 1 had a pretty pitted up push buttonI have only repaired 2 of these PTO clutches. But both needed the steel button in the center of the clutch. In both cases the tractors had apparently set idle for some time & the buttons had rust pits in them & even though you can polish them up the imperfections still prematurely wear the fixed graphite button on the actuator lever