The federal government announced that those residents (both Mexican and foreigners) that own a vehicle that was not legally imported, can regularize its status until December 31 this year. To do so online, in Spanish only, go to: https://www.gob.mx/sesnsp/es/articulos/regularizacion-de-vehiculos-usados-de-procedencia-extranjera?idiom=es
To locate your REPUVE (equivalent to the American DMV), look at the addresses below.