This is a remix of DerPit design. I created a conduit to run the switch wires from the power switch enclosure, across the back of the printer and then through the 40 x 40 channel.It just snaps in place and protects the wires as well as keeping them away from the communication cables. You need to rotate the y-axis stepper motor 90 degrees to allow for future access to the stepper motor connector. The wire size was determined by an electrical engineer friend to be 14 gauge (North American size) or 1.628mm AWG. The wire connectors are insulated (important) and are available pretty much everywhere.
Once the conduit and switch plate are printed and the step motor is rotated the wiring takes less than 10 minutes including crimping.