That's good to know. If nothing else, cardboard works well to ensure it will fit. The wall is a partial (about 7 feet wide) and there are speakers, subwoofer, etc. Physically, the space won't support a 75" display even if I wanted one, but a 65 inch will fit.
On a completely different point (and again probably naive), my center channel speaker is around 6 1/2 inches high and sits on the top shelf of a unit that holds my receiver, etc. The unit is a bit off center and I would want the TV to be centered on or over the unit. If I mount the TV on the wall and the mount was centered on the wall (assuming the studs are centered), can the TV be hung off center on the mount so I can center it on the unit rather than the wall? (I hope that makes sense).