I finished replacing my friends kill switch, (toggle), with a magnetic kill switch and I'm very much impressed with the way it works! I'm a commercial alarm installer by trade so I took a common recessed door contact and mounted it behind the metal dash and spliced into the wiring. So now instead of having to reach under the dash and flick a toggle switch he just sticks a small magnet on the metal dash where the hidden contact is and it fires right up, remove the magnet and it dies, brilliant idea! I know they sell magnetic kill switches but it's much more satisfying making your own!
I ditched the large magnet and used one 1/4 the size!