Now what?

There is lots of bluing and the hairpspring collar is spread quite a bit-guessing it's forced over the non-spread rivet.

Obvously, I can warm the brass to try and minimzing it from cracking. I have a sharp carbide cutter- go cut a little at a time on the bead of solder/metal until I'm at the balance wheel arm- then drive out the staff? Maybe some nice way to polish the balance wheel arm to remove the blueing - 2000 grit/4000/8000 sandpaper?

Oh New York standard sz 18, model 165.
Michael

Do I need to use heat to get the old staff out?

Now I'm kinda suspect if the balance isn't from another watch..