Real Mexican Near Pleasanton
All the cities in the area are small in size (in population and in area) compared to Honolulu, and are pretty much border to border. You cross a certain street and you're in a different city. You can go from Pleasanton to Livermmore or from Pleasanton to Dublin in a few minutes.
If you are looking for tripa and cabeza, you're unlikely to find it in Pleasanton. The only decent Mexican restaurant in Pleasanton (and I've been to most of them) is Blue Agave, which is an expensive, high end, fancy place down town.
In Livermore there are several that we like: El Charro, Taqueria Los Caporales, and El Castellito. These are authentic hole-in-the-wall Mexican restaurants/taquerias. The Spanish speaking customers often outnumber the English speaking customers. The food is good and reasonably priced.
In Dublin there is Taqueria Los Pericos. It's a local institution. Not a great meat selection, but this place is very popular.
Places to avoid at all costs: Chevy's, La Salsa, Mexxi's, Casa Orozco, El Balazo.
For what you're looking for, a trip to Oakland will be necessary. Look for threads in this forum, especially those about taco trucks.