I think we’ve been doing this wrong for a long time. And, given that you are at least the second person to have crushed a fixed cup, I think that Saint Brown’s method doesn’t work as well as advertised. I would suggest a better way that I wrote up for my local co-op. One caveat is to use penetrating oil like others have suggested.
I, like most everyone, have been taught to remove the adjustable cup first, followed by the fixed cup. We avoid removing the fixed cup because it can be difficult to remove. I propose to stand the procedure on its head. Remove the fixed cup first since it is the hardest one and the wrench needs the most stabilization. The spindle can be used in the same manner as the threaded axle in the above tool but it will allow the wrench to turn with the cup so that the tool doesn’t even need to be removed to completely remove the fixed cup.
Since there are 2 types of spindle, the procedure and fastener used will depend on which spindle is present. The nut or bolt used on the spindle can be used to hold everything in place.
Tool Assembly
The parts for the nutted spindle needed are shown here

A large fender washer, an adjustable cup, and the spindle nut are needed. Another washer may be needed to get the spacing right. The order of assembly follows







From above it should look like this

Turn the wrench as usual. If more leverage is needed, a cheater bar is needed.

For bolted spindles, the order of assembly is the same except a bolt is needed.



This method is much easier to use than other methods. The spindle stabilizes the wrench and turns with it much like a cartridge bearing does. It makes it easier to remove the fixed cup and results in less blood spilled.