1955-57 PASSENGER CAR "VIN" NUMBERS
Vehicle Identification Number (VIN): The VIN tag is located on a stainless steel plate that is spot welded to the driver's side front door jamb. Although, hard to see, Chevrolet also had the vehicle identification number stamped on the frame roughly below the drivers seat.
Digit 1 - Engine Size
The VIN may be ten or eleven characters long. The letter "V" before the first digit is the eleventh character, and denotes a V8 engine in the 1955 - 1957 cars. For cars originally equipped with a six cylinder engine, the "V" was omitted and the VIN would be only ten characters long rather than eleven.
Digit 2 and 3 - Year
Digit 4 - Assembly Plant
Each plant used their own sequence numbers and usually started with number - 001001 for 1955 and 1956, and 10001 for 1957. This number became the car's serial number.