GDay All,
I managed to get the broken ball end out of the 5-40 screw.
First, I let the whole assembly sit in the freezer overnight and then I
realised that I could remove the Nema23 motor mount by simply screwing
of the preload nut. That leadscrew is very long when screwing a nut off
by hand I can tell ya ... lol
After that I was able to get the ball end rocking in the cap screw. I
applied some heat, as now there were no bearings to worry about, and a
few gentle taps on the bench and out came the ball end of the Allen key.
Now all I have to do is wait for my Y-Axis components to arrive and I'll
be back in business.
Thanks to everyone who replied. Without your suggestions I may not have
been able to do it.