Are you crossing with the same vehicle? You might consider putting the permit unit in your wife's name. You might (key word) even be able to cross with the new passport and everything will be fine. I would not show them your old passport number. I am not sure if the fellows at the border can cancel your old permit. But remember the unit must be there for the permit to be canceled. If the Aduanero cannot cancel the permit he might want you to send a bunch of paperwork to Mexico. Takes months. Good Luck.
Moisheh
