I just got my 4805 and need to get a ceiling mount. One big question I have is what I am aiming for as far as height. I've heard conflicting things: that the lens should be level with the top of the screen and also that it should be a foot below. Which is right? Also, what do people like as far as mounts? I'm thinking of something as short as possible since the projector will be mounted on a section of ceiling that was dropped about 5 inches below where the screen will be. I was looking at the Infocus mount (mainly out of convenience) which is about $175. Is this way too expensive? Thanks!