[Ford Man]

Does that car have an internal or external voltage regulator? If it's not integrated into the alternator it could be a bad voltage regulator. Also check the water in the battery and load test the battery. A bad battery could have the proper voltage, but not pulling enough cranking amps. If the battery was completely dead you shouldn't rely completely on the alternator to recharge it you should hook it up to a charger for a few hours.

Edit: Also check the battery posts and terminals and make sure they are clean. Check and make sure you have a clean connection wherever it grounds and check to make sure the cable is tight and clean at the starter.