67 Barracuda headlight switch wiring?

I believe that"s a ground. It don't always make a good ground through the dash. You can prove it by taking a 'continuity tester" set to Ohms and check resistance to the steel end. It should have the same reading as touching the probes to each other.
Okay I don't see any kind of a wire for it? A quick look at the diagram if I'm reading it correctly I don't even see it on here?

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