1964

1st digit - Engine:
6 = L6
8 = V8 (326 or 389)

2nd digit - Series:
0 = Tempest
1 = Tempest Custom
2 = Tempest LeMans &( GTO )

3 = Catalina Ventura

8 = Bonneville

9 = Grand Prix

3rd digit - Model Year:
4 = 1964

4th digit - Assembly plant -
B = Baltimore, MD
D = Doraville, GA
E = Linden, NJ
F = Fremont, CA
G = Framingham, MA
M = Kansas City, MO
P = Pontiac, MI
R = Arlington, TX
S = Southgate, CA
U = Lordstown, OH
X = Kansas City, KS

1965-1971

1st digit - Division - 2 = Pontiac
2nd & 3rd digits - Series:

23 = Firebird
33 = Tempest (1965-70)
33 = LeMans T-37 (1971)
35 = Tempest Custom (1965-70)
33 = LeMans (1971)
37 = Tempest LeMans (1965-70)
37= GTO ( 1965 )
37 = LeMans Sport (1971)
39 = Tempest Safari (1967-69)
42 = GTO (1966-71)
52 = CATALINA
62 = Bonneville
66 = Grand Prix

4th & 5th digits - Body Code:
07 = 2-door sedan (post)
17 = 2-door coupe
27 = 2-door sedan (post)
35 = 4-door wagon, 2 seat
36 = 4-door wagon, 2 seat,
dual action tailgate
37 = 2-door coupe
39 = 4-door coupe
46 = 4-door wagon, 3 seat,
dual action tailgate
67 = 2-door convertible
69 = 4-door sedan

6th digit - Model Year:
5 = 1965
6 = 1966
7 = 1967
8 = 1968
9 = 1969
0 = 1970
1 = 1971

7th digit - Assembly plant:
A = Atlanta, GA
B = Baltimore, MD
C = Southgate, CA
D = Doraville, GA
E = Linden, NJ
G = Framingham, MA
K = Kansas City, MO
P = Pontiac, MI
R= Arlington, TX
U = Lordstown, OH
V = Bloomfield, IL
X = Kansas City, KS
Z = Fremont, CA
1 = Oshava, Ontario Canada

Last 6 digits - Production sequence starting at 600001
at all plants, except V8 models which started at 100001.

1972

1st digit -

Division - 2 = Pontiac

2nd digit - Series:

D = LeMans
G = Luxury LeMans

3rd and 4th digits - Body Style:
27 = 2-door sedan (post)
36 = 4-door wagon, 2 seat
37 = 2-door coupe
39 = 4-door coupe
46 = 4-door wagon, 3 seat
67 = 2-door convertible
69 = 4-door sedan

5th digit - Engine Code:

A = 213
A = 231
C = 231
D = 250 1-bbl L6 110 hp
G = 305
H = 301
H = 305
H = 350
J = 350
K = 403
L = 350
M = 350 2-bbl V8 160 hp
N = 350 2-bbl V8 160 hp (dual exh.)
P = 350
P = 400
R = 400 2-bbl V8 180 hp
S = 265
S = 400 4-bbl V8 200 hp (single exh.)
T = 301
T = 400 4-bbl V8 250 hp (dual exh.)
U = 305
W = 301
W = 455
X = 455 4-bbl V8 300 hp (455 HO)
Y = 301
Y = 455 4-bbl V8 250 hp (dual exh.)
Z = 400

6th digit - Model Year:
2=1972. 3=1973, 4=1974, 5=1975, 6=1976
 7=1977, 8=1978, 9=1979. A=1980

7th digit - Assembly plant -
A = Atlanta, GA
C = Southgate, CA
D = Doraville, GA
G = Framingham, MA
L = Van Nuys, CA
N = Norwood, OH
P = Pontiac, MI
R = Arlington , TX
W = Willow Run, MI
X = Kansas City, KS
Z = Fremont, CA
2 = St. Therese, Quebec, Canada

Last 6 digits - Production sequence starting at 100001 at all plants.