Dave -PD4104-746 was delivered new in January of 1954 as fleet number K-1869 to Pacific Greyhound Lines, HQ'd in San Francisco, CA. Obviously a West Coast bus, which is a plus. Greyhound most likely sold it to it's second owner after the summer peak season in the fall of either 1964 or 1965.
Since it was based out of SF, it was also maintained by one of (at the time) 'Hound's best service shops nationwide.
So, now you can truthfully tell folk that you own a "jen-you-wine retired Greyhound bus" when people ask - and they will!
FWIW & HTH. . .
