The 6-volt models were positive ground. In 1957, all major manufacturers standardized their electrical systems at 12 volt Negative ground. Your 58 should be 12V(-) unless it's been converted to an earlier system. Freightliner stayed with the positive ground until the mid-1960's. Before you hook the regulator up, rub a piece of clean business card stock or a paper file card between the points to clean them. DON"T use sandpaper or a file. The points open and close with a slight wiping action to self-clean, and any roughness at all will make them stick.
Jerry

Last edited by Hotrod Lincoln; 09/12/2009 3:10 PM.
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