1964 Chevrolet Truck - Rear Axle Identification

My book says that it is stamped (not cast) on the forward side of the left axle tube near the carrier housing.

It should be a code that looks like:

WF 01 23

WF = 3.07:1 ratio (in 1964) - there are 9 different codes for the 1000 series (in 1964)
01 = January
23 = 23rd day of the month

Good luck, Tim