could they do
superscript
like in the may 4 memo?
Nope. Not only that, rocklobster11, but if you look carefully the "th" is a single-strike character, meaning it was created with a special character key, and no such key existed on typewriters of the day. Also note "th" is in the print line in some instances, in superscript in others, and in mixed use on yet a third document.
What makes this even more laughable is that typewriter fonts are readily available in .ttf and the forgeries could have easily been made to look much more authentic than these rip-offs.
If you really want authentic, you can still buy good condition IBM Sleectric (originals) and IIs on ebay (my old style boss still uses them for envelopes and preprinted forms). The balls are readily available. Add some NOS ribbons to fool the experts, and you might have bought another 48 hours of play before exposure.
The second line has 111th with the superscript th, and was dated 1968. All the rest have 111th with no superscript. They were obviously written on different typewriters at different times, but it obviously was possible to get a superscript in 1968, as these are official docs.
Here's a link to the doc from the records Bush released. see page 3: http://www.usatoday.com/news/bushdocs/9-Miscellaneous.pdf