You've obviously never had a fixed cup that was REALLY stuck. Some, even the finer threaded Kingsbridge tool can't budge.

Before you hacksaw the spindle, did you try drilling the cotter? Usually, the mushroomed threaded part will snap right off, then you can get a drill into the cotter. The cotter is the softest metal of the three (crank, spindle,cotter), and quite easy to drill without damaging the other two. Once the cotter is hollow for about half the way through the spindle, a good whack with a carp's hammer on a pin driver (supporting the crank from below) will get the cotter out, no problem (and I mean a *good* whack- no holding back, no preliminary taps, just do it).

For what its worth : If you brought it over I would be happy to slap a couple of welds on it for you. I am in Eastern Kansas, just south of Kansas City.