I recently installed the Auto Pro Shift Light in my Viper, below is some information.
You will need a special Auto Pro Model Number 5340 it will have to have the pulse changed to 2.5 (this is done by Auto Pro). The Red wire goes to a switched 12 volt positive wire. The Black wire goes to a chassis or engine ground. The Green wire goes to pin C-31 on the PCM itself, this is on the Gray Module. It is the tachometer driver, and is the Gray wire with a Light Blue stripe on it. You can contact Auto Pro Customer Service/Technical Support at 815-895-8141 if you have questions.
Installation is pretty simple.