Recommendation, please, for the best Mexican Restaurant in Old Town for food and atmosphere on a Friday afternoon at 4pm. Music would be nice too if available.
Thanks,
Margo

There are so many Mexican Restaurants in Old Town. Here are a few that are popular:
Old Town Mexican Cafe, Cafe Coyote, Casa Guadalajara, El Agave, Fred's Mexican.
Without a lot of information about you personally - the ages of your party, type of Mexican food, etc it is hard to say.
Most all of these (with maybe the exception of Casa Guadalajara and El Agave) are fairly touristy, party places but the food is good and atmosphere is festive and fun. As I recall Old Town Mexican Cafe hand makes tortillas out front and cooks them on a large grill.
Really you can't go wrong. If you are able to be there at 4 pm that is very early for dinner you could stroll along the main street and choose one of the restaurants on site. I don't think you'd have trouble getting seated. But I would check what time many of these restaurants open for dinner. Most are open for lunch as well.

Have been to both Old Town Mexican Cafe and Casa Guadalajara and preferred the former. Found the food at the latter pretty pedestrian, though the strolling mariachi players were a nice touch. The food at the former was notably better, though have heard they can be inconsistent.

We've had pretty good luck at Cafe Coyote. The salsa was nice and flavorful, tortillas handmade, and the carnitas were very good. Old Town Mexican Cafe was pretty bland whrn we ate there - went once, never been back.

Best Mexican Restaurant in Old Town
https://oldtownmexcafe.com/
EL AGAVE RESTAURANT. Mexican Cuisine in San Diego.
Casa Guadalajara Best Mexican Restaurant & Cantina Old Town San Diego California

All of the above are touristy, popular and have similar food, often hand made tortillas, some times roving Mariachis, with the exception of El Agave which is probably a little more upscale.

Just to answer the question I asked--We ended up at Casa Guadalajara about 4pm after flying in from the East Coast. The patio was full even at that hour. We enjoyed the Margaritas and I had a great Chicken, Avocado and Black Bean Salad. The atmosphere was Mexican with many tropical plants.
No music at that time of day.
Margo

Thanks Margo for checking back and letting us know.

I like the foods at Casa Guadalajara. Their homemade flour tortillas are really good. The place has a nice ambiance also.