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 (2.56)
CK Positraction (2.56)
CL (2.56)
CM Positraction (2.56)
CN (2.56)
CO Positraction (2.56)
CP (2.73)
CQ (2.56)
CS Positraction (2.56)
CT (2.73)
CW (3.31)
CX (3.07)
CY (3.07)
CZ (2.73)
KA (3.55) small ring gear
KB Positraction (2.55) small ring gear
KC Positraction (2.73) small ring gear
KD (2.73) large ring gear
KE Positraction (2.73) small ring gear
KF Positraction (3.55) large ring gear
KG (3.08) small ring gear
KH Positraction (3.08) small ring gear
KI (3.36)
KJ (3.55) large ring gear
KK Positraction (4.10)
KL Positraction (3.36) small ring gear
KM Positraction (4.56)
KN (3.55) small ring gear
KO Positraction (4.88)
KP Positraction (3.55) small ring gear
KQ Positraction (4.10) heavy duty
KX Positraction (3.07)
FH (2.73)
FI Positraction (2.73)
FJ (3.08)
FK Positraction (3.08)
FL (3.36)
FM Positraction (3.36)
FN (3.55)
FO Positraction (3.55)