Agreed, don't remove it if you don't have to.
If you do have to remove it, you need to mark the direction the rotor is pointed and make sure the engine doesn't turn at all. When re-installing, make sure it's as close to that marked spot as possible, and hit it with a timing light.
My oil line fix
My 100k stopped odometer fix
Brace for impact, I'm in a "modifying mood". Massive thread count inbound.