The device with the plug that goes in it is very simple. It is installed by cutting the cranking lead going to the starter and wire each end of the cut wire into the device. The device has several terminals in it, most of which hook to nothing. Two are hooked to the cut end of the starter lead. The "key" you insert has several terminals as well, and most of them are also disabled. So, in theory, the "key" and the socket have to match. Or you can bridge all the terminals on the key and it will work in any car with the socket. Or, if you dont want to go to all that trouble, just get a piece of copper the size of the end of the "key" and stick it in the socket. Other than the fact that it does not slow many car thieves down, cutting and splicing the starter lead is not a good idea. A car parked in the sun gets hot and hot wires dont conduct well. As such, if you find the starter cranks slowly, get rid of the device. I understand that the GTO has an engine imobilizer in the ECM, so unless the ignition key is recognized by the ECM, the car will crank, but not fire. If you want additional security, find a clever place to put a kill switch in the fuel pump lead. Turn it off and the car won't run. The pump is quiet enough that most thieves won't say "hey, I don't hear the fuel pump" and they are not about to take the time to troubleshoot an non-starting car.