Ok Guys, here is another question on my Farmall M. I just got this tractor recently. Someone had rewired the tractor with all the same color wiring! They had attempted to convert it to a 12 volt system but still had a 6 volt generator on it. I put the tractor back to original 6 volt system, with a positive ground, replaced the voltage regulator,and the ammeter, which wasn't working, and the tractor seems to be charging but the ammeter doesn't move either way, even when you use the lights. Can anyone tell me what to check for? I have the same problem on a John Deere B, and am sure that the ammeter is a good one. I'm not an electrical genius so I need a little advice! Thanks for any help!