1964 to 1969 Axle codes can be found on the bottom, or left or right front Axle tube next to the carrier housing. Additionally, codes can also be found approximately 8" to 10" inside of the backing plates.

CA (3.08)
CB (3.36)
CC (3.73)
CD Positraction (3.07)
CE Positraction (3.08)
CF Positraction (3.31)
CG Positraction (3.36)
CH Positraction (2.73)
CI Positraction (3.73)
CJ (3.07)
CK (3.07)
CL (2.73)
CM Positraction (2.73)
CN (3.31)
CO Positraction (3.31)
CP (2.73)
CQ (2.56)
CR Positraction (3.70)
CS (2.56)
CT (3.73)
CU Positraction w/Metallic Brakes (3.73)
CV (3.70)
CW (3.31)
CX (3.07)
CY (3.07)
CZ (2.73)
FH (2.73) small ring gear
FI Positraction (2.73) small ring gear
FJ (3.08)
FK Positraction (3.08)
FL (3.36)
FM Positraction (3.36)
FN (3.55) small ring gear
FO Positraction (3.55) small ring gear
FP (3.70)
FQ Positraction (3.70)
K2 (3.55)
K3 Positraction (3.55)
K4 (3.73)
K5 Positraction (3.73)
K6 Positraction (4.10)
K7 Positraction (4.56)
K8 Positraction (4.88)
KA (3.55) small ring gear
KB Positraction (3.55) small ring gear
KC Positraction (2.73) small ring gear
KD (2.73) large ring gear
KE Positraction (2.56)
KF Positraction (3.55) large ring gear
KG Positraction (3.55)
KH (3.55)
KI (2.56)
KJ (3.55) large ring gear
KK Positraction (4.10)
KL (4.10)
KM Positraction (4.56)
KN (4.56)
KO Positraction (4.88)
KP (4.88)
KQ (2.73)
KR Positraction (2.73)
KS (3.07)
KT Positraction (3.07)
KU (3.31)
KV Positraction (3.31)
KW w/Metallic Brakes (2.73)
KX Positraction (3.07)
KY Positraction (3.31)
KZ (3.31)