Charging problems with 1992 580 super k

I have replaced the alternator and checked all connections but still not getting any charge to the battery or instrument panel. I am not very good with a voltmeter and don't really know what to look for. I checked the belt and pulled the instrument panel out ( lost half the screws ) and still can't get power. I disconnected the ground while it was running and it stalled. Earlier, I was getting fluctuating power to the tach but now I don't get anything. Help!!!

Charging problems with 1992 580 super k