If you allow 12 volt to go through the gas gauge with out the reducer, will destroy it very quickly.
As with every rule there are exceptions.
I'll have to respectfully disagree with this statement. There is a chance that 12v will damage your gas gauge but there's also a good chance it'll do no harm at all. In another life back in the '70s I owned a 55.1 panel truck that I converted to 12v. It never dawned on me that I might need to put a reducer on the gas gauge OR the heater motor for that fact so I didn't. I put over 100K miles on the truck after the conversion with absolutely no issues of damage to the gauge or heater motor. Was I just lucky? Maybe. I'm just saying the old mantra that your gas gauge will die if you don't put a resistor on it isn't always true. FWIW I've spoken with a few others over the years who had the same experience as me. I'm not saying that putting a resistor on your gauge isn't a good idea. I'm just saying the set-in-stone 'your gauge will die' mantra isn't necessarily fact.
