[MDPotter]

If the stock gear shift you're referring to is your stock shift column, then you can use Lokar's shift linkage kit. From what I've read, as long as you have the wiring in the column to serve as the safety switch and and reverse light signal, you don't need it. Those stock switches that mount to the transmission (in the OEM form) serve as gear indicators as well as neutral safety (so vehicle won't start in gear or neutral), reverse light signal, and to tell the PCM what gear the trans is in. But if you've got a stock automatic column, it should have the wiring for the neutral safety and reverse lights. If you get rid of the switch, the engine idle won't change when you shift gears. If you're doing a cam swap, you might consider leaving it as I've heard it can be an issue with idle.