I found the toll booth at 25.52055° -103.63973° on Google Earth - I then did the Street View on Google Earth and "drove" the street into and out of the Pemex - only problem being it appears we may have to pay another toll when getting back on the cuota - but I am not sure about that. The route into the Pemex from the toll is a hard right so being in the right land toll booth is probably important. My computer mapping Streets & Trips says it is about 185 miles from Saltillo to the toll booth and then about 135 miles from the toll to Durango - but have not done it so cannot tell you drive time.
