I have one on my truck. You need a switch and a ground wire going from the switch to any clean metal to metal part on your truck. Then you need another wire running to your transmission I'll take a look at mine to see where it runs to. You do need a built trans though or else it won't really do anything.
95 cummins auto 2500 4x4 standard cab. Stage 2 transmission, 6inch stack, Cold air intake, No fuel plate, star wheel turned , smoke screw adjusted , Pusher intake boost elbow, Torque converter lock up switch, Pyro, Boost, trans temp gauges.