That's good.
I've been looking over the old instruction sheets for the 450 signal bridge where they tell you how to make connections on the base for different combinations of lights. Forget all about that. We don't have to connect lights together at all. The relays and insulated rails will handle all of that. But hold on, let's just figure out the LED wiring.
Did you keep track of which side of the LED's you hooked the wires to coming out of the signal heads? You said that you've used this type before. Are you able to get them to light up in isolation? A 9 volt battery should work. I'm not sure if they need a series resistor but I would think so (about 500 ohms).
Eventually, we will connect the leads from the signal heads to the terminals on your relay board but lets figure out which wire is which first.
