TELECOM Digest Editor noted in response to the original query:
[TELECOM Digest Editor's Note: I can tell this much; no one,but no
> one tampers with or tries to rewire the inside of a 1A2 phone. The
> wiring is just too complex. All the rewiring is done in the box on
> the wall where there is room to move your arms and fingers, _not_
> in the phone itself. PAT]
No doubt. No one ever changed the wiring within a 1A2 or 10A2 set, with the expection of installing a buzzer for intercom. But, that wasn't really rewiring; rather loosing a couple of screws to overlap u-connectors.
And, no one in the field re-wired a 1A2/10A2 KSU, other than to restrap the tie down wiring to change features, etc.
Ain't computers great?!
TELECOM Digest Editor's Note: I really do not think anything much can be done inside those phones without a lot of grief that cannot be done better and quicker at the punchdown block on the wall. I've done 'stuff' inside those phones but mainly things like remove or re-arrange the ball-bearings under the push buttons so I could get two or more buttons to stay down at one time. And once I converted a five- line six-button phone with a hold button into a three line phone with three associated hold buttons by using two of the line strips for each line, so that three buttons merely put a short on each of the associated three lines, and re-arranging the ball-bearings as needed. This was circa 1975. It was not a fun project. That was the day I vowed never to take one of those 1A2 phones apart again. PAT]