steerer tube material? i would forget trying to save the cone spacer if its really stuck, it is only held on with friction from an o ring. should come up pretty easy. cut it off if anything, slot it with a saw as close as you can and hit it with a chisel to break it. can also try to twist it with a pipe wrench to break any corrosion. after the cone spacer is off then you have the compression wedge. that is what you may need to chisel/pry to lift it off the bearing.