all you need to do to kill the engine is to join both points via a normally open switch.
the kill button (N/O) is or can be mounted on the engine and a pair of M wires sent to the 2 M posts on the key. when OFF the key shorts the 2 BLACK M wires and kills the engine.
True, but I’m thinking he does not have the original stop button on the engine anymore, so it is more of a question just where on the engine the two stop wires (that lead up to the M terminals on the key switch) should be connected… The darn vacuum cut out circuit confuses this issue. True there are two leads hanging off the engine, but they don’t look stock, so no guarantee they are connected properly… I will have to find one of Frank’s wiring diagrams, I was careful to save them when he nicely posted them for us