I read an article in the LA Times about Clarita's relocating from Boyle Heights to a place I never heard of called El Sereno. It's between S. Pasadena and Alhambra. I passed a very cool looking Mariscos truck on the way and it turned out to be GREAT.
This sleepy little taco town is totally worth the drive. Here is a fun list of most of the dining establishments: http://www.elserenoscene.com/directorydiningquicklist.html
Definitely a cool place for a taco adventure!
Here is a link for some cool pictures of Clarita: http://www.latimes.com/news/local/la-me-taco-lady-pictures,0,5363894.photogallery
And one more link for the actual article: http://latimesblogs.latimes.com/dailydish/2011/10/tacos-clarita-lives.html