Used set in good working condition. The T-77122 has pitting on the crankshaft. The T-77123 looks like new.
Fits many early GM cars.
GM used this regulator in a wide range of vehicles, and they used it for over a decade. This is the same part in a 37 Cadillac, 40 LaSalle, 42-48 Chevrolet, Buick, Oldsmobile, and Pontiac.