[Maroon 5.0 LX]

I ran two wires thru the firewall to a toggle switch under the dash from the coil. Locate the switch somewhere out of sight.

Remove the + wire from the coil, secure it to the new wire to the toggle switch. The other wire from the toggle switch goes back to the + on the coil.

This is in no way foolproof, but should slow down anyone trying to bust the column and starting it with a screwdriver.

You can get the switch and wire at any auto parts store or Radio Shack. Most any old toggle switch should do, not much current in + wire.