The speakers weren't actually in the ceiling but hung from it. I remember a few people used to do the same thing, hanging their speakers by macramé type hangers. A local bar/disco had Bose 901's hanging from the ceiling as well. I did install speakers in my daughters basement bedroom in the ceiling though. When she moved out I reused the drivers in my homebuilt living room transmission line speaker systems (to be described in another post). I've yet to repopulate the ceiling enclosures.That is something that never would have occurred to me! Of course ceiling mounted speakers are all the rage nowadays thanks to ATMOS. You were ahead of your time. FWIW I have experimented with good quality 6.5" car speakers mounted in my ceiling. Much to my surprise if one is mounted forward of you & one behind, in line, pans from front to back have almost no effect. Mount the overhead to the sides & over head pans left to right give an amazing & almost scary sensation of height.