A deadbolt would be ugly, prone to rust, etc.
What's the internal lock mod?
This is for vehicle security when parked for long periods (on a RoRo vehicle transport, at airports, trail heads, etc) on extended trips. I'm putting locks on everythng.
There isn't a set mod per se, but it's really easy to swap in a different key drum system.
If you pull off your door panelling, you'll see where the lock is, and you'll see where a slim-jim or coat hanger can slide in. Welding in some 1/2" channel (with the channel facing up to snag the intruding instrument).
this would stop the casual thief with basic tools.
Google electronic keypad locks for something more complex.
What I'm working on is the keypad idea, with an extra inline switch on the negative lead from the locking servo, and this switch ties into the stock lock drum, so even if somebody guesses your code, they still need a key to get a circuit to the motor before it'll ever work.
But, locks only keep the honest people out, as Mace said, a rock defeats a lock.
You can also install a "kill" switch on the ignition to break the circuit to the starter exciter wire or on the positive lead itself.
when I go backpacking for a week, and want my truck left alone, I throw the cable between my ignition coil and distributor in my pack, and just make sure I don't leave anything in the cab I can't afford to lose.
Good luck!
