N.M. Stat. § 67-14-3
The state transportation commission, upon receipt of a declaration, petition, resolution, certified copy of an ordinance or other clear direction from a board of county commissioners or governing body of a municipality, provided that such resolution is not in conflict with an existing statute or ordinance, that removal of motorist services directional signs would cause an economic hardship in a defined area, shall forward such declaration, resolution or finding to the secretary for inclusion as a defined hardship area qualifying for exemption pursuant to 23 U.S.C. 131(o). Any such declaration or resolution submitted to the state transportation commission shall further find that such motorist services directional signs provide directional information about goods and services in the interest of the traveling public and shall request the retention in such specified areas by the state of such directional motorist services signs as defined in Sections 67-14-1 through 67-14-3 NMSA 1978. The state transportation commission shall thereupon comply with all regulations issued by the federal highway administration necessary for application for the exemption provided in 23 U.S.C. 131(o), provided such motorist services directional signs were lawfully erected under state law at the time of their erection and were in existence on May 5, 1976. Any costs incurred by the state transportation commission in complying with the requirements of this section may be passed on to the appropriate petitioners or the owners of the signs seeking exemption.
NMS § 67-14-3