Projector Placement

I'm in the preliminary stages of planning a sim room, and want to make sure my understanding about projectors is correct. I'm looking at the Optoma GT760 Projector (http://www.projectorcentral.com/Optoma-GT760.htm). I'm planning on a 12 foot wide screen, so my understanding is that with this particular model I would need to place the projector 6'3" from the screen. Is that correct? Is the projector generally directly above the golfer? That seems to be the case, but being 6'3" from the screen seems awefully close. Thanks.

I was looking at this one also. 6'3" is also what I get for your screen width. Height is only 6'10" though.