Dear Steve;
Any switch will work, if (that word again) It's the same (electricaly) as the 'oginal' diagram/relay uses.
See; two things occur here. The engine is "killed" for half a second, while the solenoid dis-engages the OD.
You can put it (switch) under the gas pedal or on the carburator. It has to carry a lot of current for the solenoid & relay primary.
This MUST occur at the same time.
Good luck.
