60's when the changes were made. I started with CWT/GTE in 1967 and
> they were already changed and using 48/53 Full Satt.
Wasn't 1967 the year that then General Telephone of California bought CWT (California Water and Telephone for you lurkers; aka "Cal Drip and Tinkle." ;-)
I grew up in Monrovia, a CWT town. We didn't get automatic dialing until 1950, as I recall.