Yes, anything with the ECU SBEC1 will have the engine controller in the engine compartment and will have the ECU controlling charge. The answer to the second statement about the guage is a litle more involved. You primary vehicle supply for the power when the vehicle is running is the alternator, not the battery. The reason the alternators went to extewrnally regulated is because the control circuits changes and became digital. The output to control the power is actually a modulated signal that varies with load. The reason the circuit was put in the controller was because the controller had inputs for fuel and timing. This gave the controller the ability to decrease and increase the fuel and timing with the load requirements and give better milage and faster response to demand. As for the voltage reading question. Where you measure from as far as a point in the system is not really as important as long as the voltage drop for the wiring is compensated for in the guages reading. There is an adjustment writeup someone posted. As for the controller and the 5 and 8Vdc power supplies. They are regulated by 2 internal voltage regulators. The voltage regualtors are spec'd not to vary the output voltages down to 9Vdc and the controller itself is suppose to function as a system down to 6Vdc. I wouldnt recommend doing it for a extended length of time but that is design standard. I hope I answered your questions.