On the 355 that I just had, I replaced the 3 terminal alternator connector, the wires were very brittle at the entry to the connector and 1 was completely severed. There is a braided ground strap from the alternator case to an oil pan stud, nutted in place.
What's strange is that when the vehicle starts up, we get 14.5 - 14.6v, (dvom connected to B+ bus bar stud and ground post in engine compartment). With loads on, the voltage goes to 13.2 and then drops to 12.5 or so at idle (this is with lights and A/C on)