The original alternator has a generic body. Both Hitachi and Mitsubishi electric use it. They come in a range of capacities from 35 Amp up to about 75 Amp I believe. They are internally regulated which means you can just remove the old tin regulator and loop the wires to suit. I have done this just 2 days ago, fitted a 60 Amp alternator and it runs my 4 channel amp no problem, even with the lights and heater on I still get 13.5volts.