The only way I would keep an amp gauge is if you run a shunt type amp gauge. Mopar started using them on the bigger cars around 1973 I believe. The shunt carries 90 % of the load so that way not much current goes thru the amp gauge. But the amp gauge is not as accurate since it dont move much with most of the current bypassing it and you still have to run the wires up to the amp gauge in the dash and the alt output has to go on the load side of the gauge for it to work right. Myself I would just eliminate the amp gauge and go with the voltmeter as then you can run the alt output right to the battery or whereever you want. Ron