
The poles are repro MTH, acquired some two decades ago (two sets). They go for stupid money now, if you can find them. I've seen original Lionel for cheaper (albeit in a bit rougher shape). Used the Stretch Magic cord as wires in the long-shot hope that it survives (I'll likely be the first to snap the cord).
I used a homemade utility box as the terminal at one end (top), a simple loop device glued to the inside of the top of the tunnel portal at the opposite (bottom).

Simples, but a major achievement for me
I was pondering running actual electric wires over them to power some of the lights and accessories, but that just begged catastrophe.





