I've rewired 5 LGB engines to Rail Pro, all were easily done, 3 diesels and 2 Moguls. First I do away with all the LGB electrical components and discard them in my scrap wire box, I remove the electrical pickups in the trucks, or the mogul's engine blocks, plus the electrical sliders, no more track power for me. I totally re-wire the total engine with LED lighting, I use an 8-wire plug from the engine to the tender, thus each idem that is power has its own wiring, just the way I do things. Fishing wires in the diesels is not really a problem as there is not mush to fish, but in the Moguls you will have to fish the wires in the boiler between the plastic boiler cover and the engines weight, this part of the engine does not really come apart once it is glued at the factory. You could reuse the factory wires, but I chose to run my own wires and I like everything uniform and I was replacing the Headlight to LED and I did add engine side marker lamps to the front of the engine. My engines are pretty highly modified to give them a different look from what LGB did, but you can still tell they are LGB engines. All my new wiring was smaller then the LGB wiring say 22-26 gauge, but the engine power wire was 20 gauge if I remember. I purchased my miniature wiring plug kit from eBay as well as my LEDs. And yes, you will only need two wires from the engine block to power the engine, I know there are three, but can't remember what the third on does, nothing for your Rail Pro. I tried to post pics here, but this forum does not really support easy pic posting of pics, too much BS to post them.
