Thats basicly the idea, drill a small hole in the rear of the headlight, and run 1 wire back to the motor terminal that comes from the Tender. You can solder the other wire to the backside of the headlight if its not painted or you can clean it. The whole body of the engine is the other half of the electrical circuit. I have heard of guys using a stiff solid wire as a boiler hand rail to supply the power to the headlight. The real steamer boiler handrails were electrical conduit and if you look at pics, they will terminate in a box of sorts, then a flexable electrical cord will run over to the headlight. Watch the opening scenes in the Emperor of the North, and you can see the cord going to the headlight on the 19. Cheers Mike
LHS mechanic and geniune train and antique garden tractor nut case!