I´ve used a small plumbers hack saw (one hand) and cut a notch right across the the bolt and the yoke, used a screw driver and screwed it out. Mine was in there kind of loose, threads were well oiled.
Another possibilty for bolts that aren´t real tight in the threads, is cleaning the bolt (really well, solvent and wire brush), using a dab of soldering flux, a welding rod, a battery and a pair of jumper cables. You can sometimes get the welding rod to tack to the bolt, just enough to ease it out of there. Want to arch/spark the end of the welding rod onto the bolt and get the battery cables off fo there fast, when it takcs or the rod will turn red hot and melt (use gloves). If you miss the end of the bolt and weld the threads, things go downhill real fast from there. Works better with 24 volts (truck batteries).