I bought a used REL SHO S/3 to add to my Magnepan's 1.7i and used this video to set it up and get dialed in: REL setup
It absolutely blew my mind, how better my system sounded, highly recommend. If you have a Magnepan, get a REL.
Away from the corner, closer to the speaker and closer to the side wall facing the listening position or on the room diagonal.