This is a very basic question, but this is the first time I've gutted a bathroom. When I pull out the shower stall, what do I do with the shower supply lines? There is no cutoff at the wall like there is with the toilet and sink, so I would assume I need to cap the lines somehow. These are the newer plastic lines. Also, do I need to do anything with the three drain pipes to block sewer gas, or will the water in the pipes remain and do the trick?