[jasonL78]

I would pull the gauge out. I had the same problem with my original Tach on my 68 L78 nova. I would shut the car off and the needle would stay up around 1000 RPM. I removed the Tach and found some small amount of surface rust on the needle wiper asssembly. Cleaned with a soft brush I even think I lubricated it and never had a problem with it sticking after that.

Same car with console guages I had my amp meter show what your is. I found the contacts on the voltage regulator were stuck. I changed it and that problem went away. You said you have already changed that. As for cleaning and zeroing. We used to demagnitize the amp meters on the welders at one of my last jobs when they were reading incorrectly. But they had a zero screw, not sure if this amp meter does?

Just my 2 cents if its worth anything.

Jason