I criss cross the west and northwest sides of Chicago a lot, and based on at least those routes, I'm convinced that the vast majority of Mexican restaurants these days fall into 3 catagories:
1)
Mangonda stands2) Mexican seafood places
3) Mexican seafood places that are BYOB
Happy Pollo falls into number 3, but in addition to all that Nayarit style goodness--the bracing green salsa, the gratis ceviche, the garlic bread, langostinos and such; here's also grilled chicken that's pretty decent (in this style, it aint Peruvian). All in all, it makes for excellent chowing, especially gilded by the fact that you can BYO.
We'll be there @ 7 PM in a few weeks--September 16. Hope you can join
6000 W Grand Ave - Grand and Austin. There's parking.
Think Yiddish, Dress British - Advice of Evil Ronnie to me.