I finally connected power to the first piece of track that’s laid down. First thing to test, the uncoupling action using an actual engine. Worked pretty reliably. The video below shows one of the test runs. The car uncoupled successfully each time and when the engine picks up and pulls the car through, there weren’t any inadvertent uncoupling.
Here we have UP 298 bringing an out of place Port Huron & Detroit car to an empty spur. After spotting the car, the engineer realizes that there is no industry in this town yet. Making a mental note to have a word with the dispatcher, he picks the car up again and starts heading off the way he came in. :-)