Conversion from manual to dial was by no means an indicator of how
> "busy" an exchange was. There were other factors as well. As
> mentioned in another post, it was practical for Bell to have manual
> pay telephones in some resorts into the 1970s. Plenty of busy small
> towns had manual as late as 1962, probably requiring a huge
> switchboard. In thinking about two towns I know of, I realize they
> might have been busy during the day, but virtually empty overnight.
My hometown, Cle Elum, Washington, was cut over from manual to SxS in the summer of 1966. Much of my present interest in electronics and telco equipment can be traced back to that summer. I spent many hours watching the WE techs install the switch and I carted home vast piles of scrap to play with. I was about 14 at the time.
Anyone traveling on Interstate 90 through Washington might be interested in stopping at the telephone museum in Cle Elum. It's in the orginal manual exchange building and it was the labor of one local woman to preserve as much of the manual system and equipment as possible.