That statute of Elvis atop the Azteca Mexican Restaurant and Crooners Lounge (pictured) says a lot about what's inside. More Elvis: Records, posters, pinball games, videos, and, well, you name it. I got seasick looking at it all. The place is Elvis Mania Incarnate.
Fortunately, the Tex-Mex food—available both in the restaurant and the Crooners Lounge (the bar named for the singer)—is very good and fairly reasonably priced.
Azteca is located on Main Street Garden Grove, which is (I'm assuming) the preserved first business street of the city. More nostalgia.
The restaurant is only a few miles from Disneyland and Angel Stadium, so if you're in the area, Azteca is worth a visit.
No sightings of Elvis impersonators while I was there. Hopefully, there won't be any if you go either.