I did that. The hole where the push button was is now used for my EGT/boost combo gauge. I used the base of the old push button as a connector into the stock wiring. The wires on the shift lever have to be extended to reach the stock wiring. The button is a simple push to make and release to break so there is no polarity problem. You also have to rig an indicator light. If you use an LED you have to get the polarity right for the light. You will need a wiring diagram in order to wire the button and light correctly. Best to have a Dodge service manual. The green light on my switch panel in this picture is the OD indicator light. Email me if you have any questions.