Thanks Nick.

I am using 4, M3 Ceiling speakers for the ceiling. I did not want to cut holes in my ceiling or try and rout wires through all the floor joists, so I built some boxes the speakers mount to. The boxes are attached to the ceiling. Roughly 8.5" height. I was limited to where I could actually place them in relation to the seats. The back row is directly overhead. The front row is 52" forward the back set, and at an angle towards the seats. The M3C's do have tweeters that can be "aimed" as well. I'll play around with that some if needed. That part of this Atmos project is done.

I'm using On-wall M3s for the surround and surround back channels. I have a door that's in line with the seats, so I have no choice but to mount that speaker forward. I'm happy to hear that will not be a problem.

As a couple of these wall mounts will be prone to being bumped by folks walking in/out of this room, I will most likely need to remove the driver and add a second attachment point. IE: screw though the speaker, into the wall......

I sure hope all this is worth it. Atmos really changes all the rules on speaker placement, and type.