I want to change the shower head but when I went to unscrew the existing shower head it did not remove by unscrewing. It has been on since the original in 1962. It looks like it is pressed in the shower bar. When you unscrew the head it leaves the ball on the shower bar that makes the shower head rotate. Do I need to change the shower bar in the wall to get a new shower head? Can I do that without tearing up the wall?Does the shower bar unscrew in the wall easily? Someone, please help! Where is Richard when you need a good plumber and have no husband anymore to help you? Thanks alot!!