The Stovebolt Site Forums The Parking Lot Big Bolts 56 GMC 1.5 ton: 6 or 12 volt?

I believe GMC held on to 6 volt one more year than Chevy did. Weren't they Positive ground too? Pull a bulb and check the numbers on them. Think a dash bulb of 55 is 6, or back of headlight should say voltage if you pop one out. Generator tag sometimes says? OR color of it means something.