If you have seen the Moab movie, then you would have seen them trying to replace a loose bolt in the starter on my truck. Well it wasn't lose it was snapped. After the truck made it back here to GA I climbed underneath to evaluated the damage. I was imbarassed that I had not cought the previous shotty maintenance of the starter instalation. The one remainig bolt had 3 over size nuts used as spacers.
Next after removing the starter I proceeded to easy out the snapped bolt When I did I found I had two bolt ends on my easy out. same thing on the hole that the other POS bolt was in. I guess some previous owner, could have been a Marine. Just drilled into the snapped starter bolts and tapped threads in the smaller holes.
So after two new Chevy starter bolts from a local parts store it is as good as new.
To add yes this is very common especially if someone has not used the third bolt/nut at the motor mount.