Making a car difficult to steal

I came up with the idea of putting a battery disconnect under the dash to isolate the ground and setting up another batter in the trunk that fires an ignition system through the body.
So you disconnect the ground, get out of the car and remotely activate the ignition in the trunk that is directly connected to the body of the car.
You would have multi thousand volts flowing through the whole car looking for something to jump to for a ground.

Do you think you could steal a car, or tow it away if it was like holding onto a sparkplug wire to get within a inch or so of touching it?