When Trampas leaves Mexico with the bull it has solid wheels. When it arrives back at the ranch, the wheels have spokes.
Oklahoma wasn't a territory until 1890. Before this, it was Indian territory. But on the map, while showing Trampas' journey to Mexico, it showed "Oklahoma." Post-1890's era is too late for the genre of this movie.
When Trampas and the three Texas Rangers left Larado to look for the missing train, the scenery shown was Joshua plants, native to the Mohave Desert regions of Calif, Arizona and Nevada only, none in Texas. Also the scenery shows saguaro cactus, native to the Western portions of the Arizona desert regions only, again, not found in Texas.
When Trampas and the three Texas Rangers left Laredo to look for the missing train, the scenery shown was Joshua plants, native to the Mohave Desert regions of Calif, Arizona and Nevada only, none in Texas. Also the scenery shows saguaro cactus, native to the Western portions of the Arizona desert regions only, again, not found in Texas.