Originally Posted by
HillRider
Center drilling a 5 mm bolt to allow use of an EZ-out is tricky at best. Is there any stub still sticking out of either end? If so you could slot it with a Dremmel and a cut off wheel and try to remove it with a screwdriver.
If there IS a stub, try using a pair of locking vice grips on it before slotting it . Then do what hillrider says. If that fails, your only option is drilling it out. If the drill fails you may still be lucky enough to get a tap through it and have the threads hold. I've never had much luck using easy-outs on high torque m5 snap-offs like that.