Tub drain/overflow help!
I would not use any compression fittings, they tend to leak and cause clogs, i would use all glue fittings. They sell waste and overflow kits that are all schedule 40. simply have the drain in place (1"1/2 or 2"pvc), set tub, level. when all is level and set where you will like the tube, get some plumbers putty and push metal drain in place, take threaded female shoe(the 90) that is in kit and thread on to metalic drain from bottom of tub.(pipe dope wouldn't hurt on metal threads, you might need someone to put pressure on metal drain while you thread 90 on the bottom of tub, thread as much as possible, not all is neccasary, you can finish tightening when all the connections are glued.). Now simply aim the 90 towards the pipe you are using for drain. take measurment from inside the 90 to the front of pipe, subtract 1", cut the pipe to size, glue in to 90. know line up the 90 with pipe in it towards the drain. take the fitting you are using(2"x1"1/2x1"1x2 tee for a 2" drain or a 1"1x2 tee for a 1"1x2 drain pipe) eye it up with the pipe coming from the 90, and cut drain down to size. this is where it will get kind of hard. You will have to glue all respective joints at one time and manuever the pipes into place, some brut strength will be needed, but not to much that you will crack the pipes. after connections made you will have to plumb vertically from your tee to the overflow, if drain is not centered to your overflow hole, some offset fitting will be needed 45's or 22's, make sure to plumb the overflow snug to the back of tube, also make sure you go back and tighten shoe of tub so that the plumbers putty oozes out this should also give you proper grade from tub to tee. It sounds hard but just use some commen sense and you will be fine.