I managed to take some pictures of our Tektronix Smalltalk machines today: https://multicores.org/pictures/Tektronix_440x/
Both 4404s are identical, including the firmware versions in the EPROMs. The 4406 is a bit harder to disassemble, this will take some more time. All of the photos inside this directory are released into the public domain (and I should get a tripod and better lighting...). Trying to get our ancient EPROM programmer to work now... -- Michael