Shown below, Kory and Joe, the owners (and installers) of My Custom Theater, as they get ready to start work on Day 1.
At that point, they started running all the wires. This means running the speaker wiring, the screen control wiring and power, and the HDMI video signal, from the lower wall cut by the equipment, up to the screen cut-out. From that point, the power, and control, for the screen, as well as the speaker wiring for the three front speakers (built into the screen housing), exits the ceiling, while the power for the projector, and the speaker wiring for the two rear surround speakers (in the projector housing), continued, through the ceiling, to the cut by the projector mount.
That didn't take long: Day 1
By the time the dry walling was done, it was about 3:30 in the afternoon. Total time so far, five hours and fifteen minutes!
By the way, during all their work, I naturally had to come in and out of the room to see what they were up to, asking questions (I can be a disruptive force), to a greater depth than most would have (afterall, I had to write this), and general kibbitzing, not to mention interrupting to take dozens of photos of the work in progress.