You can't go scrub-a-dub in the tub - at least not comfortably so - if your shower faucet is leaking, or if your current tub valve is stuck and not letting any shower water come through. If your shower is broken beyond repair then your best plan of action is to take the whole thing out and reinstall your shower stall. We know this big - and potentially disasterous - procedure has been parodied many a time on popular TV sitcoms, but it's actually realizable if you're careful and follow the steps in this video exactly.
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