Thanks for the replies.
I don't know how Id cut the head off as there is not much room to work under there....
So what is the process for removing or moving the swingarm enough to get a new bolt in the top?
Not sure what install a stud means but Id still have to get the old bolt out.
My guess would be to remove the swingarm. A lot of work but I think that is the only way. The only other way would be to cut the head off of the bolt and run the new bolt in from the bottom, but I would NOT recommend doing that.