Rear axle tag?

This is the rear axle tag for our 1972 Mustang convertible. From what I can tell on the Foridification site, the ratio is 2.79 which matches the other info on the car. The WCZ-V, however, is listed for 67-70 Mustangs. It is not illuminating as to what the rest of it means. The 930B is supposed to relate to where it was made. The middle number on the bottom row should show something like D2? for a date code if it were original. I wonder, however, if the 8 stands for 1968 and it is missing the letter codes for decade and month. If anyone has pointers for more info or can read it, it would be appreciated. The engine turned out to be from a later year, so no surprise if other stuff was changed as well.

Thanks in advance!

Forgot to note I wanted to be sure to ID the axle size, from what I read on Foridification, this would be an 8 inch.

Thanks!

https://www.differentials.com/technical-help-2/differential-identification/

WCZ-V2 is a 71-72 Mustang 8" open differential with 2.79 gears. 

1LB - built 2nd week November 1971

2.79 - gear ratio

8 - 8" differential

930B - plant code

Huge thanks you for both answers! That means it is likely original to the car, so worth rebuilding one of these days when we get tired of the small leak. We needed to know the size as we are replacing the rear brake lines and it matters for that.