I remember my brother and dad replacing the alternator in a ‘77 Rabbit and ending up with an extra bolt. Never did figure out where it belonged, and the car ran for at least another 10 years.Did you have pieces left over when you were done?
See, it's a little known secret, but manufacturers routinely add extra whozits, whatchamacallits, and thingamabobs when they build things. These extra parts often get out of whack and ornery, and you have to go in and remove them. Then everything works fine...