I have a Lionel conventional steam engine setting on a sideline in engine house. I wanted to allow the light and smoke unit to work without the motor when I applied track power. (I cannot conventional) I just cut the wires to the motor, now I have the light and smoke unit operating. Adds realism to the engine house and locomotive. Because of no smoke fan the smoke drifts from beneath the engine and a small amount from the stack.
Not sure if a fan driven smoke unit will fit, I will check that out with Gunrunner later. 
Bob
