Originally Posted by rpainter
can you get a cut-off wheel to it? If the nut is not useable anymore why not take the cut-off wheel and cut a side of the nut off to relieve the pressure on the threads.
Rather than trying to do the entire job with a cut-off wheel, use the wheel to take it down, but stay away from the axle inside..... then, again with the PB Blaster, wire brush, possibly heat, dance, stick a chisel into your cut and try to hammer it in enough to start spreading the nut.
I usually make at least two cuts on opposite sides, even better is 3-4, plus the chisel.