Somewhere there should be a wire that connects to the ignition coil, then runs out to the open area where all the wiring is.. When THAT wire is grounded out, it kills the spark.. so find your original shut off switch, and just attach the wire from your new switch, to the old switch, or into that coil wire some where.. If you look at the system you should be able to figure out how it's all working... When the switch is turned on, there is NO CONTINUITY so the engine runs.. shut the switch off it makes contact and grounds out your spark... You just need to figure out what wire you are grounding to kill the engine.. it should be half hidden under your blower cover somewhere..
