Originally Posted by Stuart_Giles
As BC59 says you do need a shunt if you aren't going to peg the ammeter needle when you start your truck with a slightly flat battery.

Just connect the two wires from the shunt to the ammeter. then connect the other ammeter wiring to either side of the shunt. Look at this photo, the two wires go off to the ammeter, the connector block takes the other wiring which would normally go to each side of the ammeter itself. BTW, the shunt in the photo was made for a 20A ammeter on an old Austin car. you need 3 100W 1 ohm resistors in parallel to shunt the ammeter on a chevy truck, I run this setup on my truck with a 68A alternator.

Wow, that's way different than the 12ga wire I was going to use as a shunt. Why would that guy tell me to use a plain old 12ga wire instead of the 3 resistors you are advising to use??