Wait...really? Or do you mean you have no shortage of exposure to Mexican-US culture? It aint the same as being there.
Kinda like I laugh at anyone in the US who says they are Irish American. Yeah, like hell you are...unless you moved here from Ireland. Go back and tell the Irish you're "Irish American". Most will just call you a fat assed American and make you buy them a drink.
I looked up the Aztec Stadium. It doesn't seem to be in the heart of Mexico City. Seems to be on the southern skirts.
You sure that's where you want to go to watch a football game? I mean it's not in the old part of the city. Please forgive my ignorance as I'm using google maps to do the research and I've never been there myself.