Elecrical problem On 1972 Duster

Ok ,put another 6 hours on Duster today. Started at battery, Cleaned posts and block and frame ground , That bleeding is going thru complete car, even the radio fades in and out , here is questions , Battery shows 11.7 volts , Alternator only charges at 12.5 and hardly any at idle . Shouldn't the alternator be close to 14 volts and battery at 12.6 ? All grounds are good , even took steering wheel off and cleaned the turn signal switch . I am going at battery and alternator next , Starts good and runs down road , but seems needs more voltage. We ran a new wire from at drivers front of door to the rear lights , no brighter. Thanks for ideas !