I am guessing but there are two sides to this switch. The purpose being to enable the forward or reverse contactor (if you are in low or high gear). It is cost effective to run the power to one side of the switch and jumper it to the other side. Then there should be one return wire from EACH side of the switch. Therefore see which is the hot wire per a meter or the wiring diagram and that should be jumpered to power the other side.
George
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)