Flickering Headlights

:D HI there,
I have a 1990 Ford Taurus GL(3.0). About a year ago my headlights and interior lights began to flicker so I thought my Voltage Regulator(VR) was bad. Upon replacing the VR my lights still flilckered so I bought a Remanufactured Alternator. After installing it, tho, my lights "still flickered". I thought the new VR I purchased at a low price may have had the wrong Amp rating. I then made the mistake of disconnecting the ground on the VR. This did stop the flickering but ended up frying my car battery because it was being over charged at 18+ votls! Of course, the new VR was now shot because it wasn't grounded, so I installed my Old VR, made sure it was grounded, but my lights still flicker. So, was the Alternator damage by the above? When it is activated by the VR, it's clutch kicks in and it makes a winding noise and has no constanct rpms. So what's the Fix?
Thanks