electrical issues can be really frustrating,keep it simple,if the alternator put out 14.1 volts on the car initially and then degrades with a load i would suspect the battery .possibly a bad cell.the alternator is telling you that you have got enormous current draw going on.when you start turning on accessories does it affect idle speed?does the engine pull down slightly? this is also an indicator of current draw.swap the battery if there is no change,pull the headlight connectors and remove them from the circuit.still no change,pull the 80 amp fuseable link and test again,if there was no charging issues prior to the headlight task i would really check that area well.was it a simple plug and play swap or did you have to modify or repair the wiring? bones