Had to pick up some solder because my mechanic friend forgot some from his work but he fixed the bad connection on the Champion grader. It now shows about 13.5 volts on the gauge in the cab. I think that should be sufficient I won't have too low of volts for the electronics in the transmission. Also found out why the fuel gauge doesn't work. The sending unit was broke off. Hopefully Jade Equipment will have one and it's not too expensive. Also hoping they might have a wiring diagram for the tach. Have a couple wires but not sure if they're for the tach or not.
if that fuel sender is absurdly expensive, check Gregg Dist for a Stewart-Warner sender. i believe SW makes some that are adjustable for tank depth and SW usually has the resistance spec
I think I just need to know what brand of gauge to get the right ohm range for a sender. Gauges have no name on them. I thought maybe VDO because that's what the tach is but can't find any the same looking online. Would like to know where the tach hooks up electrically? Apparently runs off the alternator but I can't confirm that. If someone has a wiring diagram for the tach eould be great.