I've all but completly torn out my old tub/shower and have found a
(shower only) model from Sterling ( at lowes) that I like. It has a
center drain but my bath has a left hand drain.

Is it very hard to relocate a drain? Also, I have a window in the upper
middle of the shower wall. Is it very hard to modify these kits. You
have to cut them to get the shower head etc through, so I imagine there
is a way to modify them without damage to the entire wall piece..?

A problem I can see would be most of these kits push out from the where
they connect. That is , they connect at the top flush with the studs but
push out from the wall below there to make them more flush with
surrounding dry wall or tile..

So, if I cut for the middle of the wall window, I will have to fill in
below that area and some how glue the thing around the window.. ?

TIA
CP