If you have the locking tool that looks like a bent piece of metal, then you have the right one. Slide the curved end into one of the grooves of the armature. It should be a nice tight fit. The other end will then bind up against the bell housing itself. When removing the fan pulley, remember that they are left handed threads; therefore, turn the fan pulley to the right in order to loosen it. If your tool is straight with little stubs on each end, then that is not the correct tool. That tool is used for the 500 series models up through the 1-CR. Hope this helps.