Bill;
I had to blow the pic up real big to see, but honestly it looks close to being an interference fit, key.
Good luck getting it out. The good thing is that they key material is usually a softer material than the shaft, to act as a sacrificial lamb if something goes haywire.
You could try a cold-rolled chisel and NOT a cheapo one either, you'll need to get in under the very front of it with a good 3lb sledge.
Otherwise you could merely use a good chisel to shear the top part to be level with the shaft and go from there.
NICE looking motor
The chisel and sledge has worked for me in the past, getting the tip up is by far the hardest part a good center punch may help with getting at it.
Best of luck
Bruce S