OEM/Stock ECU
If you are on a stock ECU or an ECU where you do not have any extra/available inputs/outputs then I recommend you get the wiring harness. The harness makes thing easy, because it's built in module will auto-unlock the reverse solenoid when it detects the transmission speed is less than 4 mph. It has a built in speed conversion tool that is tunable so you can make your factory/OEM dash/speedometer display the proper speed. It also provides provisions for the reverse lights and keeps all transmission related wiring in a clean and simple installation package.
Get more details about the T56 wiring harness
Standalone ECU
If you have a capable stand-alone engine management system (Haltech, Motec, etc etc) and you have available inputs and outputs then you should just get the pigtails. You will need to use your ECU to convert the speed signal from the T56 pulses, to your stock speedometer pulses. And then use the speed input to unlock your reverse, I recommend using a conditional, something to the effect of "if under 4mph, then send 12V to the reverse lockout"
Go to the Pigtail Kit product page.
