Just so you know, it isn’t actually a bolt. The shaft has a threaded section beyond the arm bushing with a nut that retains it. So, you should be able to carefully cut the nut off with a small Dremel cutoff wheel similar to what I did with the arm bushing. You may be able to then just run a die over the threads and replace the nut after the new arm is on.
Thanks for telling me that. Ive been out of the game too long, Im a little "rusty" I knew those were held on with a nut but frustration got the best of me this time. I did dremel it off and got the new one on tonight:guitar2:
side note if anyone finds this in the future- the nut is m6x1.00