Crossing basement shower supply lines

If you use certain single handle shower valves, then you can reverse the hot and cold in the valve rather than cross the piping. To valve it, you need regular valves and PEX adapters into them. Copper will usually be easier. Use a drop ear elbow fastened to a wood spacer to hold the shower head. Do not use PEX to the shower head, use copper instead. : 1) I am installing a shower in our basement and (because of the shower valve : postion), I have to cross over the hot and cold water supply lines down to : the shower valve… any advice? I plan to use pex pipe to use the job : because of its easy use and flexibility… anybody have any advice ?: 2) I also plan to put in stop valves for this pex pipe… what should I use : to valve these pex lines?: 3) should I use cooper instead?: 4) What kind of fitting can I use to secure the shower head pipe? what : about the supply lines sticking out of the wall? (a copper strap with holes : in it? Ive seen them before…)