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[opie1knobe]

You could always unbolt the tires and take them with you, thus eliminating someone stealing your wheels or stealing your truck.

I personally would go with a starter kill relay and a hidden switch like Tallavanna Said. If someone wants your truck bad enough consider it gone. They will steal it and leave your expensive alarm sitting in the parking space. Most crooks however want to get it and Go, no delays, if they cant get it quick most will leave (probably tearing up the seats and dash along the way just because they are pissed) Perhaps the best idea is let them steal the truck, that is what insurance is for.