Stripped ARP 12pt.

It would really help to post a pic of what you are dealing with. You said a nut on a stud, but I'm not aware of (or can't think of one) you would have to remove to swap the cam.
Re'
BTW, I would have grabbed a sharp chisel a long time ago and it would have been taken care of.
Sorry man,
Shane
http://www.sears.com/shc/s/p_10153_12605_00952166000P
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