The camera and receiver I bought together at York. You can get them cheap on eBay. It outputs with RCA jacks. I bought the 7-inch monitor on eBay also.
The camera runs on a 9 volt battery. I convert the AC 18 volt track power to DC 9 volt for the camera. The drum head is running on track voltage. Using a LCD calculator it told me what resistors to add to the LED headlight and 2 side lights: wired in series.
I would like to give more specifics but this was my first project like this. I'm hoping it won't burn out. I also used capacitors for the LED headlights and the 9volt DC camera feed.
The boxes to hide the electronics were from a Lionel car that came with them; I air brushed them in PRR color after prepping and cutting them and added decals.
I used craft sticks cut and weathered with India ink then stained for the floors and light housing.
The wood beam was to hide some wires. I added a winch to it and my daughter glued on some people
I did not write down anything I used for electronics as I built it so I can't explain much more. It does work very well. The frame was from a beat up Williams passenger car, I should have used a shorter frame to look better. I used a constant current charger power supply to change the AC to DC. $6.00 shipped on eBay. Thats it.