Most gunsmiths would cut the old barrel to relieve the torque required to remove the old barrel and avoid the chance of messing up the receiver.
Oh, yes I did mess up a receiver about 30 years ago too
It was not funny at the time however and took some time to get it straight again. It happened very quickly, it does not take much to make it happen, trust me.
Not all are hard to remove, but some are and require extra special attention.
If it is a new barrel, you are going to need a setback tool to get the sight aligned properly. You can do it by hand but this requires a slow hand and much more time.
Good luck
Vern