pull the wheel pull a stud out of the pulley and go to hardware store and pick up some bolts and washers a long with red lock tight
measure from the bottom of nut to the end of the stud that should give you length.
Ask for the hardest bolts they have. Stop at auto parts store and rent a torque wrench. Ask them how to set the right pounds just to be safe
If the nut comes off thats OK get pulley out of way and with vice grips back the stud out
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