The horns are wired with one ground wire running from horn neg to the mast bearing. This bearing has a wire incorporated into it. There should be a connector to connect wire coming from horn to the mast bearing wire, coming out bottom of column. The pos horn terminal gets wired to the pos on ammeter. I think any fused hot will be OK. Do you have a horn relay? I thought we were talking 1951 1 ton? What exactly is this truck and what year is it?

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