This is the third Vandalia West story, called "Atraco en la via Ferrea" in Spanish. The credits in Chilean original have been removed for this translated printing. The stories in Far West were split into two parts across two issues. This story probably appeared around issue 160.
There is a story of the same title in Two-Gun Kid 59 (Marvel, 1948 series), April 1961. While it is by the same team of Lee, Kirby and Ayers, it does not seem to be the same story.
"Selecciones Ilustradas - Derechas Reservados - España". The main character in this story is called Bill and appears to be "Bill el sonríente" (Spanish) or "Bill, o Sorridente" (Portugese)—"Smiling Bill". There is no feature title. The series was created in the early to mid-1960s and appeared regularly in Hazañas del oest (Toray, 1962 series). Those stories were typically six pages rather than 20 pages as this story is.