Illuminated Destination Signs

Does anyone know how one can make illuminated destination signs like the one in the picture below. I did recently purchase the HO Silverliner V’s from Imperial Hobby Productions.

I guess it depends if you can make your own decals.

I would carve out the numberboard face, and make a box behind it from strip styrene. Drill a hole in the back of the box for a 1.5V micro-light or LED. Use a yellow bulb or LED. Carefully cut a window from clear styrene or acetate. Make a decal with the destination sign using clear decal paper. Use a black background and white lettering, white prints as clear on almost all printers.

I appreciate your information. It was very helpful. Can I skip the box part and just mount it on the compartment of the Silverliner shell as shown below? I carved out the destination sign compartment which was originally molded. By the way I’m working on number boards for some locomotives. I will get the number decals from Microsale Industries. Will clear styrene make good glass inserts for the number boards? or should I get some other clear plastic. If so where can I get them from?