Water shouldn't be a problem here as the switch is inside the car, I had a look at Snett and the trouble is that the only way we could get the switch to kill the engine was to have the feed from the alternator connected to the battery side (naughty). There are wires connected to the smaller spade terminals on the back, but in the time available I couldn't work out exactly where they went, but needless to say they weren't having the desired effect. It's made harder by the fact that Simon's car has a lot of wiring for a 2cv racer, and very little, if any, of it is original.
Am I right in thinking that to cut the alternator output the secondary switch(spade terminals) could be in line with the +ve feed to the regulator, or in the wire from regulator to alternator? Or alternatively the switch could be used to cut the supply to the ignition coil? Is there a 'correct' way of doing it? As it stands one of the switch terminals went to earth, I wasn't sure on the other.
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