AF switch wiring

I have what I believe to be a pre war O scale/gauge American Flyer that was my fathers. The only stuff that remains is the train itself and a pair of switches and the switch controller which I have rewired. Originally it had red and green wires to match the colors on the switch but for now I've just used some wire I had. I've included pictures of the stuff below in order to maybe get an answer to the question how do they wire up? There is a red wire for the red switch location of each switch lever and a green wire for each green switch location. So two red and two green. There is also a single black wire that comes out of it. The switches themselves have two wire post on them which have a bit of red and green paint on them. I've looked online but only seem to find manuals for the post war stuff which is more advanced. My guess is they wire into the transformer somehow but I'm not sure just how or where that lone black wire goes. Thanks for any help, guesses or dead on answers you might have. I think it's from around 1940 since my dad probably would have been the right age for a first train.