"Flipping" film over to show trains operating in the opposite direction is a technique that wasn't confined to low budget TV programs like Wild Wild West.
The opening credits in the 1988 Mike Nichols feature, "Biloxi Blues", show a dramatic aerial shot of a former Savannah & Atlanta 4-6-2 crossing the lift span at Van Buren, AR with a period passenger train. The lettering on ex-DL&W commuter coaches used to recreate the WW II era scene is clearly visible.
The film's closing credits are set against the backdrop of a train crossing the same bridge, supposedly in the opposite direction. However, if you look closely as the aerial camera pans down. you wll see that the Lackawanna lettering pm the coaches is reversed - the mirror image of what was shown in the film's opening scenes.
As an aside, Nichols spent so much time shooting and reshooting this scene that the bridge owner - Arkansas & Missouri - was fined for tying up Arkansas River barge traffic. The lift bridge is normally in the "Up" position and is only lowered when a train has to move.