axle code de-coding

I'm fairly familiar with Fords door tag coding but am unclear on one thing. The axle code only indicates ratio, not the axle itself, correct? I would think they would somehow specify 8 or 9" in cars like the Mustang, Fairlane and Torino.

Yes, the ratio is there, and I believe the axle size too... Or maybe it's just some other designation numbers... There are more than just the ratio though...

The door tag tells you posi or not, ratio. Number=ratio and none posi, letter=is posi and ratio. Rare is a posi 8". Then you go to the diff tag for more indepth info. Build date, ratio, bearing size, posi, ring gear size.