disconnect a spark plug wire?
Remove the distributor wire and take it with him.
I believe you are right - I was told that when I got my first car.
If I remember right it was just the wire from the distributor to the coil.
Yes. Car will not start without it.
For what its worth I thought your answer was better.
shorting the ballast resistor.
Removing the rotor.
Bingo, buddy. We used to swap a plug wire with the coil wire, in the distriutor cap too.All the wires were there, and the rotor too, but it wouldn't start! Heh heh.
The rotor removal disables the car unless the thief has a spare rotor. Nothing is obvious when the hood/bonnet is raised. The owner simply replaces the rotor when he returns.Sounds like you had a lot of fun in the school parking lot!
undo a battery cable?
Puke in the carburetor.