Can anyone give me some advice on how to remove a push-on stop from hard 1/2" copper. This valve is a push-on connection with a push-odd pull-on control with an intergral supply line. The connection to the valve body has started to develop a leak. Ihave tried rotating the valve while pulling on it to no avail. The valve is mounted very close to the wall which precludes cutting it off and replacing with a compression valve without opeing up the wall and replacing some of the pipe.