Got it. Great pics of the tool. This picture says it all:
I did not realize there are more than one slot(s) in the tool. Makes total sense now. When I did mine rude and crude - ON THE BIKE - without a tool (it can be done, but it's difficult) I used a little anvil in back, and a flat punch to round the head over a bit.
Yep - I'm buying that Park tool.