Comment by Crunchified

Connections Museum in Seattle is where they should look. As deep as it gets! They maintain working switches dating back to over 100ya, massive documentation libraries, and artifacts and parts out the wazoo from telephones to teletypes to outside facilities and equipment to momentos and books and on and on.

If Connections has a weak zone in its collections, it's in the post-ATT/1984 era of cell technology and computer networking. Open Sundays 10-3.

https://www.telcomhistory.org/connections-museum-seattle/