I've been trying to figure out the same thing, a good thread I came across was:
http://67-72chevytrucks.com/vboard/s...=474293&page=2
The general theme here is there isn't much you can do to prevent a simple hot wire on these old rigs, but I like the idea of GPS tracker, at least gives you something to show the cops, or your own vigilante justice if you know what I mean.....
