Nope. LOL. At least not now. When I move my battery to the trunk, it will get a kill switch, and yes I may set it up to ground the alternator out.
Ever shut off a lawnmower engine by grounding out the sparkplug? Now, that was always fun. Hints. Don't use your bare hand and don't be hesitant about it. LOL.
While putting idea out there. A self powered alternator, like the GM 10SI and 12SI series, can cause the same type of issue. The factory solution was to wire a resistor in between the ignition feed and the field wire. A diode will do the same thing. So where this is going is... cutting the power to ignition is probably the key thing - whether its coming from battery or the alternator, keeping it from the ignition will kill the motor.