Flickering Lights

Additional information: 1. Using electronic regulator like Mopar came out with in 1969. Purchased from Quick Start. 2. When engine is at idle, about 800 rpm, the dome light, instrument lights, do not flicker. 3. When engine is brought up to about 1200 rpm the dome light, instrument lights begin to flicker (rapid bright to dim). 4. Turn on headlights lights stop flickering. Turn off headlights lights flicker. Head lights stay steady, do not increase in brightness or dim. 5. Have four (4) grounds from engine to frame and engine to bulkhead. 6. Have made sure that voltage regulator has a good ground. Even tried running ground from regulator to negative post on battery.
7. Did have charging system checked at parts store. Told that alternator was working but regulator was not. Thinking about taking alternator to different parts store and have checked.
8. Voltage meter needle jumps around like a kid on a pogo stick.