Do your markers turn on with the track power, or can they be independently controlled?
That’s very cool, btw.
You could probably modify an engineer or fireman figure to look like someone sitting with a phone. Cut the arm off (with appropriate HO-scale anesthetic of course and re-attach it in a different position and then stick a piece of wire bent like a phone receiver painted black, in its hand.
The markers are battery powered (AA) with a miniature on/off switch.
If they were track powered I’d use a simple one or two function decoder to control the markers. But to make these track powered I would have to add some form of power pickup (wipers), and I’m not a big fan of friction on the last car of a train.
Cutting and modifying an engineer figure is probably what I’m going to do for the cupola rider.
I have several versions of cabeese on my road. Here is one of two Athearn BB Bay Window Cabeese in NYC Jade Green I use frequently. This one and its brother are lighted. I have to find a way to put markers on it (them).
Here is the same caboose at night:
I used brass wire wound around the axles for pickups on this one. Its brother has modified Kadee coupler springs for pickups. Details on my website.