I'm trying to remove the back half of my exhaust. All i need to do is get this one nut off the bolt, and it will just come off... the problem is on the other end of the bolt is a kind of nut that is round, not hexagonal, and is supposed to have a little "finger" that sticks out, and hits the exhaust pipe keeping it from turning. That way you only need one wrench to undo the bolt. The problem is that the little finger broke off, so I can't remove the nut because it just spins the whole bolt... any ideas how i can get the nut off? Sorry about the camera picture.