Actually, it depends where you will be flying in Mexico. If your itinerary includes MEXICO CITY (MEX), then YES you will have access to all of the ACs that you encounter on the day of travel.

Mexico City (MEX) is the one and only exception to the "North America" lounge access rules.

You are allowed lounge access when traveling to/from/through MEX if:
a) you are traveling in J (with status or without)
b) you have PLT or EXP status (regardless of COS)



**NOTE: If you are bypassing MEX and flying directly to another city served nonstop by AA, such as CUN, then you will NOT have any lounge access.