Looks like you got a workout!
I've had a few things repaired there. Recently GM AV refreshed a tube phono stage,and it came out performing better than new.
"meet the owner George Meyer"
You spoke with the owner Morris. GM is long gone. The original shop was on Santa Monica Blvd.
Morris is a cool, no BS dude. Upon picking up my phonostage, Morris declared it "BADASS!" Meaningful, from someone who's heard their share.