Yes, I have my X motor wires running down the bottom slot of the top rail, held in by one of those covers. Can't put them in the top slot, because the cover interferes with the carriage wheels. I have my X switch wires running down the top slot of the bottom rail, under another cover. I set my bed zero point to be bed all the way back (away from you as you face the front of the machine) and X zero to the left. So my X switch is over by the X motor.