I have a tub spout htat is just roached and i need to replace it badly. The problem is.the old spout is about 40 yrs old and coneected way inside.the one I need to install has the threaded portion right at the end of the tube. unfortunately it is not an option to rip out the tile and replace entire tube. Is there a way to cut and rethread the tube w/o opening the wall and removing the tube? Thanks!