If you are referring to running wires from the CABIN to the trunk, then you can run it along the floorboard, underneath the plastic door seal covers, and then between the rear seat and the rear quarter panel (BEHIND the seatbelts... ..)
Just remove the screw that hold each plastic piece to the floor, and then run it inside the small groove you will uncover.
Run power down one side, and RCA down the other.... not together
Ray