Amp gauge shunt

I currently have the dash on my work bench and just finished painting the dash fascia and installed new inlays. Now concentrating on the electrical. I am installing a new solid state IVR and re-soldering connections. I know the factory harness needs some help especially due to the electrical system changes resulting in the alternator upgrade. As for the amp guage it was ether re-solder it's connections and test, or install the guts of a Sun Pro volt guage in the ralley amp gauge housing. The shunts and heavy guage wiring worked on my Power Wagon, and I did not baby it. Just trying to explore my options. Considering I need to replace the charging circuit, keeping the amp guage seems the best.