The power bracket will work. Try to hit a stud so you don’t have to use wall anchors. Probably about 2 ft from ceiling is where I’d start. If you have a way to shift them up and down without mounting to the wall first you can try different heights and see what sounds best

LFR1100
VP180HP
EP600
M3 In Ceiling x 4
M5OW
M2 - Atmos rears
ADA1500.5
M3 Outdoor Speakers
ADA 1000.8