Hi Seth – like you, my wife and I are both RP card holders and sometimes drive down although mostly fly in anymore as the wear and tear of the long drive back and forth has taken a toll.
There was a lot of confusion over this issue last year, especially right after Mexico started stamping the FMM in visitors passports at airports instead of issuing the paper one. FMMs at border crossings have continued as always.
Some people were saying that INM officials insisted that PR holders still get an FMM but that has not been our experience. We flew out of Cabo right before Christmas and they stamped the exit in our passports but we were not required to turn in an FMM when they saw our RP cards. Returning last month we just got into the line for Mexican citizens and were waved through with just an entry stamp in our passports when we showed them our RP cards.
We were told by INM that when we are going leave and enter by vehicle at one of the border crossings, just drive through and show them our RP cards if asked.
Now here comes the tricky part.
We were also told that if we plan to either fly out and drive back or drive out and fly back, that it was important that we get an exit entry stamp from INM at the border to keep the ratio of entry/exit stamps over time always equal to exactly one, as that was something that INM would look at from time to time at airports.
Now if there is no INM office? That’s a tough one as we have only crossed the border at places with INM offices during their operating hours. If I were you, I would ask that question at an INM office.