I am building a full bathroom in the basement. The drain/control valve side of the tub is against an exterior wall. When I mount the control valve as instructed, flush with the finished wall, and slide the tub unit in, the control valve sticks out too far. All three walls are framed up already. Is there a trick to get this to work? Is there a different design of control valve that would work better? Mine is a Delta.

is there a cartridge in the valve?
if there is remove it. that should give you clearance..

The cartridge is removed. This is an issue with the control valve body itself. The plastic square piece should be flush with th finished wall, however there is the tube that the cartridge slides into that hits the tub/shower.

The black square cover does not have to be flush with the finished wall, or tub surface. Mount the valve body deeper in the wall.

Take out studs on the opposite wall, to shift the enclosure away from the valve when sliding it in.

ditto

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