"The rank abbreviations used in the memos are wrong - Or maybe my mind is wrong about when the military changed the rank abbreviations. But best I can remember they are as follows: 2LT; 1LT; CPT; MAJ; LTC; COL; Etc. I do not think any military person would use the abbreviations as indicated in the memos. If this person was the commander he would have used LTC, Commanding for his signature block."
You're Army, right? The abbreviations you use are a giveaway.
In USAF from the 1970s, as I used them, it was 2Lt, 1Lt, Capt, Maj, LtCol or LTCol, Col or COL, etc. NO Lt Colonel would have typed "1st Lt" Bush!!!
Lt Col Killian would have signed his name (even in private memos he was writing for himself) as shown in the one authentic document used for comparison.
J. Killian, LtCol, USAF (or TexANG?)
Commander
However, your point is valid. The memos did not use the typical USAF abbreviations for rank, nor did the memo writer format the signature block as a commander would do.
And he would not have typed 111 F.I.S. - no one used periods.
Army is correct.