So we didn't lose any shelf space on this Lack bookshelf (which isn't being sold anymore?!) I moved the upper shelf just over the TV. The shelf is held in by small pins that are screwed into the outer frame, they do not rest on the pins, that would be too easy. The outer frame is solid so my installer simply drilled new starter holes (drilling the holes was simple, measuring where to drill the holes not so simple).
This is a progress shot. I need to tack the cables so you cannot see them as you do now.