I have a suggestion for your Rail Chief Train set (00706) Please change the color of the front headlight and back headlight on the GP40 locomotive to white. My front and rear headlights are RED. ? The train runs great but I'm kinda disappointed in your choice of lighting.

I found on another forum that you have to remove the fuel tanks. Then you will see two screws. Remove the screws, shell drops off.  It took me a greater part of a day to finally Goggled and found the forum.