Hey Dan, If the arm and spindel are still mated together,then, place over a large open vise. Let the spindel hang between the jaws and close enough so the cup straddles the top of the vise. Wrap a shop towel around the cup so it won't be solid against metal. Get a drift pin larger then the threaded hole,but,smaller then the square taper hole and knock the snot out of the spindel. One or two raps with a hammer should free it. The older Stronglite was 1mm larger then standard. I know there are taps to renew standard threads as MTB riders are rough on them,but, try Yellow Jersey in Brooklyn?? He may have the over size tap. I'll get his address and send it later today. Good luck. Dickey Dickey's Recreation Room