I don't think an electric impact will get it off. You'd need a pretty decent air compressor and gun to get it off. I recommend (if it's driveable) to bring it to a tire shop and ask them to take it off. Then tighten it where you can take if off at home. If it's not driveable, get a chain wrench (grabs the pulley) and then a long breaker bar and use your leg muscles. Good luck!