Houston Texas Pemex gasolinera has been in business for 2-years. It's lower price made headline photos scandal in Mexico. More than 50% of the gasoline in Mexico is now refined outside the country. The hard core Mexican refined gasoline is found from south of Mazatlan and south of Queretaro to Guatemala. But 100% of all of Mexico Premium grade is USA. UBA diesel has punched big holes into the Bajio but not along the coast south of Manzanillo.
But no USA Pemex will see a drop of Mexican refine fuel. Totally wrong vapor pressure and additive package. Shell Houston provides that gasolinera and Valero SF Bay area furnishes west coast Pemex.
Next shot is reducing sulfur in gasoline to <5 ppm