Yeah, I've seen that signage during multiple visits to Deming (it's near a favorite hot springs resort), and flagged it as an issue before I took over usanm. Problem is that NM 497 doesn't appear in the official route definitions, and hasn't for a long time. I wrote it off, and would continue to do so, as yet another case of goofy NMDOT route signage. Deming seems to have a lot of it, including remnant US 70 and US 80 route signage on the I-10 business loop (US 70 officially follows I-10 through Deming, and US 80 has long been truncated to Dallas TX).