This is related to my question on trying to diagnose what's wrong with my alternator, but I feel it stands alone as it's own question.
I ordered a new rectifier based on the findings listed in the linked question, but when I opened the alternator up I noticed that the brushes looked really short:
I took a screen shot from a video of someone replacing the brushes on a similar model Mitsubishi alternator:
Just as a quick recap, it's an 80 amp alternator and the field control unit ( ECU does voltage regulation ) has a 14.3 volt set point. At 2100 rpms, it's maxing out at about 58 amps and between 12.6 - 13 volts while at the same time drawing about 3 - 5 amps from the battery as well.
So looking at this it makes me wonder if my problem may just be that the brushes are too short and it's not the rectifier?
What are typical symptoms of short brushes?