I've got a quick story...

I have a 1973 Charger that some punks broke in to trying to steal the car but in there hurry they stole the radio instead...

I wonder why???

After I relized the took the gauges as well off the bottom of the dash. That had a AMPERE gauge in the set. When they pulled the wiring out the amp gauge killed the power to the entire car and went black! There was no way to start the car after these wiring were pulled...

It saved the car but it made a mess out of the wiring under the dash...

 

The cigarette lighter switches, ash tray switches and headlight switches are useless. Everybody knows about them.
I have an alarm connected to my air horns for when I am in earshot (about 1/4 mile!) then I have a hidden switch hooked up to the neutral start switch and a main power switch hooked up to a toggle with a threaded lever and a nut loctited on it so it feels like a screw and this is totally hidden from sight, you can only reach it with fingers.
Then I have another switch that is momentary that is mounted somewhere to the right of the steering wheel that enables the starter when pushed (also hidden), you have to reach over with your left hand and hold it on BEFORE turning over the starter.

While at work some guys punched my doors to unlock them and trashed my steering column and then ripped all my stereo wiring out from under the dash trying to find the kill switch wires when they realized it wouldn't start. I stood about 200' away and watched them struggle while on hold with 911. There were two guys in the cab and one truck backed in next to mine with a guy behind the wheel and he was watching me. I looked around the parking lot for a rock or something to heave at the truck but there was nothing. My insurance paid over $1500.00 to repair the truck which included body work on both doors, they punched holes through both doors. But Hey! They didn't get it.

Use your imagination and mount a switch somewhere totally unusual. I install kill switches for many people and I try to never install in the same place twice. No vehicle has been stolen with one of my swithes on it.

Of course, this doesn't help if the thief is using a tow truck. All you can hope for is that the truck is dumped when they can't find out how to get it to run.

 

Hook up a CO2 bottle that fills the cab when it is tripped. If they can get out before asphyxiating, then it is their luck....




No, don't actually do this! If it went off on accident while you are driving, you would be dead instead of some thief.

 

If you really paranoid you could mount the ignition or starter kill switch and for extra security measures , put a 3/8 shutoff valve between the lift pump and injection pump....if they do get it started by finding the switches, it will stall and they'll have to start cracking some injector lines open...not likely.