I tried once to get a fixed cup off and gave up. I tried Sheldon's gizmo and it didn't work for me. I was going to replace an old Zeus BB with a modern Campy Chorus 10 speed. Instead I cleaned and repacked the Zeus BB and put the Chorus crank on it and it has been absolutely perfect ever since. Dead quiet, quieter than my sealed Mega-Exo outboard BB, and completely smooth. Not bad for a 30 year old BB/axle. The Chorus 10 made the chain dead silent too. It's a good thing they were both square taper and they matched.