Initial Problem:
1) Car Hesitates, primarily on acceleration
2) SRS light Illuminates
3) Battery Light, Brake Failure light, Parking Brake Light, Bulb failure light come on while driving - bright at low RPM, dim at High RPM

Action taken - replace voltage regulator on alternator with a used part from local junkyard, until a new part can be ordered

Result:
1) Battery Light, Brake Failure light, Parking Brake Light, Bulb failure light extinguished, BUT
2)Car starts right up with a jump, however SRS light comes on after several minutes idling, and gas guage slowly moves towards empty, and the car dies.

Do I need an alternator?

Thanks!!