[swk550]

Thanks for all the help.

I have discovered when I unplug the wiring to the alternator built in voltage regulator, the current draw to the battery stops.

I don't know how much draw there is as the voltage test light does not light from battery red terminal to disconnected red positive cable nor does it light from disconnected red cable to ground. I do measure over 250ma with my voltmeter.

I bought a new voltage regulator assembly and grounded it to the engine. Same thing happens. So I reinstalled the old alternator and tested the engine. Now with lights and fan on, at 2500 RPM, the best the alternator can put out is 13.2 volts (14.2 volts is normal). This is the high output alternator Ford installed on the 91 Mustang 5.0 engines. Do I need to replace the alternator next?

I do plan to install a battery cut off switch. I have read various opinions on weather to install it on the positive battery cable or on the negative ground cable. Since my battery is in the trunk and my ground cable is in the rear of the car, I can install the switch in the trunk on either cable. If I were to install the switch in the transmission tunnel or under the dash, my easiest wiring modification would be to install the switch on the red positive battery cable. I welcome your input on this one.

Steve K