Highest Amp Alternator For a 72 Duster

I run a 500 watt amp and a 250 watt amp using the 125 Amp alternator but the amps are powered directly using a very heavy wire (think it's 2.0 fine wire welding cable). The radio turns the amps "on" using very low amperage and the battery (alternator) runs the amps directly (through a big fuse). I have two 250 watt 10" speakers and 4 50 watt 4" speakers in the car.

treblig