American Flyer locomotives
Here are my 5mm warm and 3mm cool LEDs used as headlights on American Flyer locomotives. The steam locomotive has the 5mm warm LED. The American Flyer Baldwin Diesel has the 3mm cool LED used as headlights. These are great! All you have to do is mount the light behind the existing lenses and hook them up to the motor. Presto you have BRIGHT headlights even at slow speeds!