Cody
Looks really nice. If you want to put an Ammeter inline you don't need a resister but you need a shunt.
I might have something you want, I basically made a guage box for testing which has a 1-15 Volt guage and a Amp guage that goes up to 100A. Could take a pic of it if you want, I could let go of it real cheap as I don't use it anymore.
All you have to do is wire it in where you want, my guess is somewhere around the voltage reg.
Bryan