I figured it out.
I set up a pin under "config" / "ports and pins" / "input signals" from the menu in mach3 to be my probe pin. I then made two connections for the wires coming from my probe on my printer cable. 1 wire goes to the common ground on my cable and the other is on pin 11 of the cable. You can use pins 10-13 or pin 15 for the probe.