[jdorour]

IRIS,
The M in your VIN indicates the point of manufacture. in this case the M is for Lansing, MI. The engine code is stamped on the right cylinder head.

Engine codes for 1966:
330 V8 250 2-BBL MT 9.00:1 QI
330 V8 250 2-BBL MT 9.00:1 QJ(HD clutch)
330 V8 --- 2-BBL MT 8.30:1 QK(export)
330 V8 250 2-BBL AT 9.00:1 QA
330 V8 250 2-BBL AT 9.00:1 KQA(with K19)
330 V8 250 2-BBL AT 9.00:1 QB(with A/C)
330 V8 250 2-BBL AT 9.00:1 KQB(with A/C & Kl9)
330 V8 --- 2-BBL AT 8.30:1 QC (export)
330 V8 310 4-BBL MT 9.00:1 QU
330 V8 310 4-BBL AT 9.00:1 QS
330 V8 310 4-BBL AT 9.00:1 KQS(with K19)
330 V8 320 4-BBL MT 10.25:1 QV
330 V8 320 4-BBL MT 10.25:1 QX(HD clutch)
330 V8 --- 4-BBL MT 8.30:1 QY (eport)
330 V8 320 4-BBL AT 10.25:1 QN
330 V8 320 4-BBL AT 10.25:1 KQN(with K19)
330 V8 320 4-BBL AT 10.25:1 QP(with A/C)
330 V8 320 4-BBL AT 10.25:1 KQP(with A/C & K19)
330 V8 --- 4-BBL AT 8.30:1 QO(export)

VIN DECODE for 1965 THROUGH 1971 MODELS
From 1965 to 1967 the Serial Number identification plate was attached to
the left front body hinge pillar directly below the upper door hinge. From
1968 to 1971 it was attached to the top of dhe instrument panel on the
driver's side and is visible duough the windshield from outside the car.

2nd and 3rd digits - Series - 31 = F85 L6 (1968-71)
31 = Cutlass L6 Hardtop Coupe (1971)
32 = F85 V8 (1968-71)
32 = Cutlass V8 Hardtop Coupe (1971)
33 = F85 V6 or L6 (1965-67)
34 = F85 V8 (1965-67)
34 = Vista Cruiser Wagon (1966-67)
35 = F85 Deluxe V6 or L6 (1965-66)
35 = Cutlass L6 (1967-71)
36 = F85 Deluxe V8 (1965-66)
36 = Cutlass V8 (1967-71)
38 = F85 Deluxe Vista Cruiser (Custom) (1965-66)
38 = F85 Cutlass (1965-66)
38 = Vista Cruiser Custom V8 (1966-67)
38 = Cutlass Supreme V8 (1967)
42 = Cutlass Suprcme V8 (1968-71)
44 = 442 V8 (1968-71)
48 = Custom Vista Cruiser V8 (1968-71)

4th and 5th digits - Body code - 07 = 2d Club coupe
17 = 2d Holiday coupe
27 = 2d Club coupe
35 = 4d Station Wagon
36 = 4d Station Wagon
37 = 2d Holiday coupe
39 = 4d hardtop sedan
55 = 4d Vista Cruiser
56 = 4d Vista Cruiser
57 = 2d hardtop coupe
65 = 4d Vista Cruiser
66 = 4d Vista Cruiser
67 = 2d convertible
69 = 4d sedan
77 = 2d Club coupe
87 = 2d Holiday coupe

6th dlglt - Model year - 5 = 1965
6 = 1966
7 = 1967
8 = 1968
9 = 1969
0 = 1970
1 = 1971

7th digit - Assembly plant - B = Baltimore, MD
G = Framingham, MA
K = Kansas City, KS
M = Lansing, MI
R = Arlington, TX
Z = Fremont, CA
1 = Oshawa, ON Canada

Last 6 digits - Production number (sequence)