interesting [I like they call the brow above the windshield a "smart cadet peak"], I'd think polarity would be mentioned, especially if it was mixed, but they do indicate V8's all were 12V, and I've always heard the positive ground ended with 6V in 55
I see as well at Keith's, the shop manual listed as 55-59 has a date of 1956 [so it's actually a 56-59 manual], and shows neg ground in schematics with no mention of 6V ... always did think GMCs were haywire
Bill
