I used Stereo 1 in Northridge for my 2018 Explorer. Very happy with the work they did and the prices were as good or better than any of the other half dozen or so places I seriously looked in to. I had 2 amps, a dsp and a bunch of speakers installed. Everything worked as it should when they were done.
What I found was a whole lotta crappy places that didn't know squat about customer service and were more about looking and acting cool/important. There are some guys that do custom work and I gathered very excellent work, but their schedules were all full. Probably not the case now in virus-time.