A friend's dad let me have an old RAC Timing Light of his and I am a bit confused. Both clips are yellow, so there is no indication of positive or negative poles. It also has two cables for the spark plug and wire but I'm not sure how to hook them up. Any ideas?
I got these pictures from some other thread. I don't have the packaging or instructions or any of the other tools. Just the light with the four wires.
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