We're remodeling our master bath and am down to the Moen shower parts. I'm attempting to remove the metal elbow extension where one end is threaded for the shower head and the other threaded end goes into the wall. I've removed the shower head with no problem, it is the end that goes into the wall. I'm very nervous about forcing it as I already broke a pvc pipe for hot water on one of the faucets requiring a costly plumbing repair. Anyway, I've put a set of vise grips on that elbow and have attempted to unscrew it in a counter-clockwise fashion but it does not want to turn. Since it has been in since 1995 I'm sure there is both corrosion and plumbers tape at play here. Any suggestions? Is there a special tool to remove this? (See attached pic).