If it is a soket head then it is simple, just drill off the head with a drill that fits into the soket of the head. When the head is gone the part[muffler,valve cover, whatever]will come off. Then you can grip the shank and screw it out.Flat heads are a little more difficult to drill off, but hey who said everything was easy. Sometimes we have to put a little more expertise[effort?] into it.