It shows up in the text:
Most of these later axles (10 or 12 bolt) would have also been stamped with the 1970 style three digit application code (e.g. CBT instead of just BT).
I thought it would have been confusing to add the extra codes in the table. But next time I edit that page, I'll try to make that part clearer.
Yes, got your email. Have been doing house projects....
Thanks!