You can get kits from any electrical place like Dick smith or Tandy but a dead simple way of killing the starter it to cut the purple wire running to the starter motor and run it to a switch hidden somewhere in the car. This is ofcourse a cheap and simple way of deterring theives but easy to source and locate the wires if you get under the bonnet if you are one of these low life pricks that steal cars and ruin someones pride and joy.
Apart from that I had a Black widow car alarm put into my VL for a total cost of $200 which included the front doors central locked. I bought the car alarm off ebay (do your shopping and compare prices) and saved $150 for the same alarm as the major stores could do it for. Thats the best way of doing it but for something quick and easy to fool the average person into thinking that your car wont start, do it as I have said above.
For the Fuel injected cars, you can run two switches. One to the fuel pump, and one to the starter. No fuel, no go, and no starter wire, no start
Easy
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