The Epson 8350 has excellent lens shift and zoom which makes mounting easy. It will work great on a shelf against the wall behind the viewers. The thing to do is to mount your screen wherever you want it, then set the projector on the shelf (or anywhere else in front of the screen), don't angle the projector toward the center of the screen if it is not at the center, just point it straight ahead perpendicular to the screen, then turn it on and adjust the zoom and the lens shift so the picture fills the screen correctly. If the edges of the picture are cockeyed, that means the projector is not pointed perpendicular to the screen, so just point it more in the direction of the shorter side until the picture is rectangular like it should be. Then make your final lens shift and zoom adjustment.
Your remote should control the projector fine even though it will be behind you, just point it at the screen and the remote signal will bounce back to the projector.
I like to sit 1 to 1.5 screen width from the screen, but you can decide how close you want to put your seats. When people stand up they may cast a shadow onto the screen, but that never lasts long and is not a problem for most of us. Ceiling mounting prevents more of those shadows, but is not worth the trouble if you have the versatile lens shift of that 8350.