I was able to find the 2 earlier manuals mentioned:

RadioNerds-TM 11-485 (PDF) (33.22 MB) 4

Internet Archive-US Army Cryptography Manuals Collection (see "TM_11-485.pdf")

https://radionerds.com/index.php/File:TM_11-485.pdf

https://archive.org/details/US-Army-Cryptography-Manuals