I remember cutting in the 919-232 Sligo central office in Currituck County North Carolina in the mid 1970's. They took subscribers from both the 919-435 Moyock office in the north and the 919-453 Coinjock office to the south. The effort had absolutely everybody in the company including accountants working the frames and checking and triple checking the records. The general manager was there to supervise but was really more in the way. I was there with all of our transmission group to quickly resolve any difficulties that may come our way. This is a very rural exchange and our trucks were parked on the highway shoulder for quite some distance around the building.
We had all the trunking up and running quite some time in advance. Calls into and out of the new (AE Strowger with 101 directors) switch had been proven already. The dial-operator circuits had already been connected to our manual cord-board operator center and were thoroughly tested in advance.
There was a small army of cable splicers in the field including many contractors. We had all the extra space in the building filled with folding tables equipped with phones and seperate numbers for each field unit to call-in updates. Each phone was manned by a person with queue sheets for that portion of the cut.
We had plug-in protector modules on the new frame, so it was relatively easy to push them in. This was also a fairly small office, maybe 800 lines. In the old offices, the heat coils could be easily stripped out by running a screwdriver up or down the frame then sweep them up with a broom.
While I was with this company, we cut in several new Strowger exchanges. I can remember one case where a large bank of two-pole toggle switches was installed on some spare frame verticals. Each line was pre-wired through it's own switch in advance of the cut. It was a simple matter to throw all the switches at cutover. I was not on duty for this cut, so I don't know the details. Sligo was the first so it got a bit more attention than the later ones. I've never seen that many phone trucks in one place before or since. They even had units from surrounding territories there. Everything went almost flawlessly and most of the extra help wasn't needed. However, the management at that time was very concerned with quality of service.
There were also frame blocks made with slide switches built-in. The slides were out for pre-cut and a board held against a whole bunch of them could be pressed in at once for the big cut. After the cut, they were removed and saved for the next time. These switches made for a whole lot of frame work before and after the cutovers.
I think a special directory addendum was issued for Sligo.
Sligo was also our first office with all digital carrier. Moyock and Coinjock were open-wire Lenkurt 33 and 45A and some Lenkurt 45BX on microwave. There was even a microwave/open-wire junction with Lenkurt 45A/BX.