Les,
You are saying the same thing as me when above I mentioned Foxtrot +buzz number ( no. on nose).
And no fighters would us the CVW codes (AG, AA, NK, NF, etc etc ) they have painted on their fins. Other-role a/c may be using them, though it sounds unusual and exceptional to me, but I do believe you as you were there. Some of these other role a/c only have a single number on the nose and that may have something to do with it, as it would sound funny to call the bird "5", all by itself. RD5 would be more pleasing if the code were RD. Do you see what I am getting at?
I also know that some final digits of the buzz numbers on the nose were never given to aircraft in the mid-eighties, to avoid confusion of some sort or because of a computer software bug--I do not remember what the men told me then on the IKE in the Med.(Pilots told me on the carriers.)
Now I do not remember if that number was 4, or 9 or whatever. That is 104-204-304 or 109, 209, 309 etc. I do not know if that policy has changed since.