X Marks the Spot?

Few fictional places in Major Dundee (1965) are given exact locations in the real world.

When Dundee asks Tyreen for a place to get supplies in Mexico, Tyreen points to a village on the map. If that is a real map of northern Mexico, the village would be a real place with an exact location.

Later, Dundee goes to Durango, probably Durango City, which is about as close to Mexico City as to the border between New Mexico and Texas,in the State of Durango.

And there is another possible precise location.

The expedition more or less follows Sierra Charriba's route from New Mexico through the trans-Pecos region of Texas into Mexico since they are trying to catch Sierra Charriba.

At one moment someone says they are 86 miles from Fort Davis, if I heard correctly, and what sounded like 50 or 15 miles from the Rio Grande. Since they cross the Rio Grande into Mexico the next day I consider 15 miles more likely.

The Rio Grande makes a Big Bend swinging south of the Fort Davis National Historic Site. According to the map they are unlikely to be any where along the Big Bend between south west of Fort Davis and south east of Fort Davis, because most of a quarter circle arc 86 miles from Fort Davis in those directions is across the Rio Grande in Chihuahua, Mexico. There is a section of the Rio Grande in the Big Bend as much as 90 miles from Fort Davis, but that would not do unless they were said to be only 5 miles from the Rio Grande.

Possibilities 1 & 2, West of Fort Davis. According to the map, a place about 5 miles east of Sierra Blanca, Texas, near Interstate 16, should be 86 miles west northwest from the Fort Davis National Historic Site and 15 miles from the Rio Grande. A place near Route 62 between Cornudas and Pine Springs should be about 86 miles northwest of Fort Davis and about 50 miles from the Rio Grande.

If they were in either place they would cross into the State of Chihuahua, Mexico west of Fort Davis.

Possibilities 3 & four. East of Fort Davis, a place southeast of Rosenfeld near Route 90 would be 86 miles from Fort Davis and 15 miles from the Rio Grande. Further north, a place about 20 miles east of Fort Stockton near Interstate 16 would be 86 miles from Fort Davis and 50 miles from the Rio Grande.

If they were in either place, they would cross into the State of Coahuila, Mexico, east of Fort Davis.

Apparently the Rebels abandoned both Fort Davis and Fort Stockton in August, 1862. But in Major Dundee the Rebels seem to have soldiers in the region in 1864.

Someone familiar with the arid Trans-Pecos region might be able to suggest logical routes for Sierra Charriba and Dundee to cross the region. It looks like the eastern and western routes would be almost equally good ways to get to Durango, especially after wandering around chasing Sierra Charriba.

Added 07-03-2019 A transcript of Major Dundee gives the location as:

It's 50 miles to the border,
and 86 to Fort Davis.

Read more: https://www.springfieldspringfield.co.uk/movie_script.php?movie=major-dundee

So it looks like the choices should be possibilities 2 & 4. If the command rode an average of 10 to 50 miles per day, and traveled from November 7 to 18, 11 days, they should have traveled about 110 to 550 no doubt winding miles from fictional Fort Benlin.