I am installing a Manchester Tub/Shower C024-0916 (http://www.cctubs.com/Products/Manchester.pdf) made by Carolina Classic Manufacturing, Inc. on a pre-plumbed concrete basement floor. The stud walls haven't been installed yet. So now there are just capped PVC pipes sticking out of the floor. The tub/shower installation drawing calls for 2 1/4" from the center of the floor waste drain pipe to the rough stud wall if I'm reading the drawing correctly. This is supposed to make the floor drain/overflow pipe vertical. This would leave approximately 1 1/4" between the outside edge of the 1 1/2" PVC floor waste pipe and the rough stud wall. I am wondering how much tolerance there is in this placement if I am off on the wall placement?

In other words when the PVC overflow pipe is connected to the Tee from the tub drain can it be re-positioned slightly if needed at the time of installation? I just don't want any surprises after the walls are up and it's time for the shower/tub installation.