I will get you some better photos showing the relationship to the seats, but yes, I put them "on their sides" so to speak.
The front and rears need to be at an angle due to my lower ceiling height of 7' 8" or something close to that. The front two are mounted the front ones on Axiom Full Metal Brackets. They are towards the front of the room a little more than standard Atmos angles to 1) allow for more dispersion across more of the seating area (not to hot spot), and 2) so that they also fall within the DTS:X range which is usually a lot closer to the walls.
The rear speakers are more close to the seating area since my 2nd row of seats are closer to the rear wall, so there isn't much difference in the Atmos recommendation and DTS:X recommendation. The angle of the speakers is a lot less because of this location. Since we usually sit in the front row, there isn't any hot spotting. For this lower degree angle, I simply used a cut piece of wood at an angle.
Anyway, here is an image from my build thread until I can get you some current photos. These front ones aren't at this drastic of an angle any more. I also have them "toed in" a hair too.
I will try to get some current photos tomorrow.