These diesel F7-like locos were inspired by set 10020, (Santa Fe Super Chief) and my dark bluish gray with white / light gray stripes train cars. The cab and booster units feature no interior details because I have no need for such items on my layout.. that and retrofitting all my trains with inside stuff would be quite costly.
The number 7301 should go on the sides of the nose just before the windscreen, while BRS (standing for my railroad's name, Brick Railway Systems) should go in the middle of the cab unit's sides, just above the fuel tank. (The engine numbers and railroad name should be made out of official printed 1 x 1 tiles.)
The rear of each of the locos feature doorways to the next engine compartment, and / or the passenger train itself.
This is with the passenger cars attached. The cars are already built in real life as of two years ago, but the engines will have to wait awhile to be built.