I would try to cut a piece of allen wrench just long enough to fit into the socket of the bolt and stick out the top of the head long enough to fit a open end on to the piece of hex. you wont be able to use a hack saw or port-a-band to cut the allen wrench, there hardened. use a cut off wheel. then try to wrench it out that way.
j/k
Glad to know I'm not the only one who does this!
