Fluctuating AMMETER/VOLTMETER (MAD)

Ok folks, here we go. I drive an all original 1969 Dart 273. I've replaced both the alternator and VR once before but one day while driving i noticed the Ammeter was fluctuating pretty rapidly between the middle and 'C' side(right) of the gauge and the headlights and dash lights strobed with the fluctuation. I kept driving this way for some time but one day it wouldnt start. I could jump start but it wasnt charging. Read some forums, did some multimeter tests and replaced the VR and alternator(it was under warranty still why not?) It worked but still had the fluctuation in the Ameter. After reading some more forums and finding the MAD electrical article about bypassing the Ammeter, I did so. I also bought a little setup from pepboys and wired in a volt meter, oil pressure, and water temp gauge. Everything worked GREAT for a few days. Lights were brighter and steady and the volt meter was reading a solid 14-16. Sometimes at high rpms it goes up to 18 on the volt meter...is that bad? Now even the volt meter is fluctuating and the headlights and dash lights are strobing again. I'm thinking to check grounds? Kinda stuck here... Has anyone encountered the same problem?