post 185 on page 19 of my thread
See the condenser has a contact point that has a spring and pushes on a set of wires that one is to the low tension wire to the magneto and the other to the kill switch one side.
Note, the other side of the kill switch is to good ground. When the kill switch is contacted, then it does not matter if the points contact and disconnect as the engine spins, as they are shorted effectively by the kill switch. This is a safer way to stop than the high tension plug wire.
A really good ground would be by using an external star tooth washer and soldered ring terminal to one of the screws through the magneto lamentations where it is used to mount the magneto next to the flywheel.
In any case the handle bars usually have an OK ground, but there is grease between the metal to the neck, so I took a ground from a bracket that is for my jack-shaft on the same platform of the engine. The engine bolts utilize split lock and external star tooth lock washers to hold it in position for a small amount of adjustable tension for a belt drive. The external star tooth lock washers then tie the metal electrically much better.
I also use a wire from that bracket straight to the tightening clamp of the push button kill switch on the handle bars, so I need not worry about the grease affecting a good ground connection. I also parallel a toggle switch that also is a kill switch, but you don't have to hold any button down. Both are there in case the other fails.