Can you bring me up to speed, can a selectric perform all the tasks needed to recreate these memos? I am under the impression that it cannot.
1. They would never -- not in a million years -- exactly reproduce the character spacing for each and every character in a modern MS Word font. The chance of that isn't small, it's identically zero (unless Monotype raced over to that Air Force base and immediately bought that particular typewriter and font ball, stored it in an airtight, oxygen-less package for twenty years, and then unpacked it to make the font today--and used a 1000x microscope to do it. I know, I've done that sort of font reproducing, and months of work with a 100x microscope and Fontographer will *not* give you exact results like they apparently have).
2. It would be nearly impossible for two memos created weeks apart to have exactly the same centering in the address at the top. Centering was done by hand: you had to type the text on scratch paper, measure it's width, divide by 2, and then move to the exact starting position on another piece of paper where you would type it again. You might get close, but you would never get it to exactly overlay as these memos do.
Obvious. Blatant. Forgery. Burn 'em, FNC. Burn 'em good.