Voltage issues

I noticed last night on my way home from work that my headlights were flickering. I looked and also noticed my amp meter was also fluxuating. The car seemed to be running fine asside from the lights kept flickering. It did not make a difference what RPMs I was running, or even if the car was moving. My 2000 Bonneville has the original alternator and 181k on her, any pointers??????

test alternator output and battery. check all battery cables, etc...

All that appears ok. I am getting a pretty steady 14.8v output at the alt with the car at idle and watching the headlights flicker. I went and checked the dash amp meter and as that was happening, the meter was fluxuating quickly from about 12-15. I also checked the voltage going directly to the headlights and it is stable at 14.4v.

Don't be surprise if your alternator goes out. Could be the brushes wearing out. I would double check all the grounds you can find.