Suggestions on routing PEX to new shower valve

Suggestions on routing PEX to new shower valve I’m looking for some suggestions on how I might re-route the plumbing for my new Delta shower valve. Currently, the copper pipe is set almost all the way back in the wall studs (see picture). I need to bring the water lines forward quite a bit to accommodate a stringer and the new valve. I’m planning on transitioning the copper pipe to PEX A. So my questions are: Where would you cut the copper pipe to sweat on the copper to PEX A barb fitting? How would you route the PEX, including drilling any new holes, to accommodate the new shower valve? I’m not 100% sure if the wall is load bearing or not so for now assume it is. Also, I’m new to PEX (PEX A) so not sure how much it can bend over short runs.