I removed the pulley and found that the inner race had walked inward. This is what happens when the drive belt is over tightened. That's probably what caused the pulley to come loose and wear out the splines. The pulley nut had lots of red lock tight and was still in place.
Notice a few splines missing on the left pulley.
The inner race has walked inward. The tool will not fit behind the race.
I ground a slot on each side with my cut off wheel. You need to be careful not to cut too deep.
This will allow the tool to fit so the race can be removed.
Removing the inner race.