Slide the rotor on the spindle and install the outer wheel bearing, keyed washer, and castle nut. SSBs supplied keyed washer didnt fit on our spindle, so we reused the original washer. (Didnt we already tell you not to throw any of the old parts away?) To seat the bearings, torque the castle nut to 12 lb-ft while spinning the rotor. Back off the nut until its just loose, and retighten it until youre just able to install the cotter pin. Now is a good time to spray some brake cleaner on the rotor to ensure theres no grease left behind.