Hi - I'm at the planning stage on remodeling two back-to-back bathrooms. In the small "south" bathroom, I want to put a tub in where the toilet is currently located (marked "A") and move the toilet to where the shower currently is ("B"). Below is a closeup of the plumbing plans for this space. The house is a 1979 north-Florida home on concrete slab (and I'd like to minimize how much concrete I have to remove!) The roof of the house is also concrete so I'm hoping the existing vents are adequate as additional roof penetrations would make this a lot more complicated. I'm looking for suggestions as the most straightforward way to reconfigure this. Thanks!