Based on recomendations from the board - I tried Taqueria El Amigo today since it's right next to my work.
You won't find a place that better fits the moniker "hole in the wall" better than here. I showed up on Tuesday and had trouble finding the place because there wasn't an open sign out (closed on Tuesdays).
I was the only customer there when I walked in probably because it was a late lunch 2:30ish, but I couldn't even find a menu - no wall menu or stack of take out's. I'm guessing most customers don't need a menu to know what they want. I was handed a laminated restaurant style menu, which was a little confusing if this is table service or not - I wouldn't think so with the size - 6 tables and a counter, but I got the feeling I should have just sat down for service.
I went with the Cabeza (beef cheeks) especiales - four small tacos with diced onions, a slice of avocado, and tons of cilantro ($5.50). Free chips and salsa was provided - excellent salsa with a good kick and lots of cilantro flavor. The chips weren't homemade and were very typical.
The tacos were fantastic - I loved the beef cheek meat - very much like short ribs as others have stated - but tons of big beef flavor. The tortillas were soft, but not soggy like I've seen. Overall very impressed and the price was great considering chips and salsa were included.
Taco & Salsa photos