Located on the top of the dash on the driver's side and visible through the windshield from outside the car.

FIRST DIGIT : Identifies GM Division (4 = Buick)

SECOND DIGIT :Identifies the series

SERIES	CODE
Appollo Century Century Lexus Regal Century Wagon Century Lexus Wagon LeSabre LeSabre Custom Estate Wagon Centurion Electra 225 Electra 225 Custom Riviera	B D H J F K L N R P T V Y

THIRD AND FOURTH DIGITS : identify the body style

BODY STYLE	CODE
2-Door Hatchback 2-Door Coupe 4-Door Sedan Station Wagon 2-Seat 2-Door Coupe 4-Door Hardtop Station Wagon 3-Seat 2-Door Hardtop or Coupe Convertible 4-Door Sedan 2-Door Hardtop	17 27 29 35 37 29 45 57 67 69 87

FIFTH DIGIT : identifies the engine

ENGINE	CODE
6-250 V8-350 2-BC V8-350 4-BC V8-350 4-BC Dual Exhaust V8-455 4-BC V8-455 4-BC Dual Exhaust V8-455 4-BC Stage I V8-455 4-BC Stage I	D H J K T U V W

SIXTH DIGIT : identifies the year (3 = 1973)

SEVENTH DIGIT: identifies the assembly plant

ASSEMBLY PLANT	CODE
Southgate, Calif. Framingham, MA Flint, MI Van Nuys, Calif. Fairfax, KS Wilminton, DE Fremont, CA	C G H l X Y Z

LAST SIX DIGITS : Represent the basic production sequence

EXAMPLE:
4	V	57	J	3	H	123456
Buick Div	Series	Body Style	Engine Code	Year	Asm Plant	Prod Code