" Yes, as someone suggested, it's connected to the wheels, meaning, I guess, one truck has two connections to "It's" rail - the wheels come up to these "frame" wires and also the track pickup. I WONDER WHY? "
The power pickup on the trucks have been done this way even back to the AC Gilbert days, I believe in part to preserve electrical contact over the turnouts or switches.
As far as the LED headlights I filed the LED flat on the front and super glued them right to the lens, but I did use the Evans Design leds that have the circuit in a very small package. Good to see that you are getting these worked out to your satisfaction.
Ray