I have a Troy-Bilt Chipper Model 420. There are 3 stationary (welded?) bolts attached to the Inner Flail Housing Assembly where the Lower Chipper Chute Assembly attaches. Two of the three bolts have snapped. What are my options: 1)purchase a new Inner Flail Housing Assembly (don't really want to do that) or 2)drill out the stationary bolts and replace. Is there anyway of getting these bolts out without drilling them out?

Thanks, Mike