They are actually screwed in place with four screws. The floor is two sheets of 3/4" plywood to extend it enough to accommodate the two chairs. The OEM couch had the seat belts so we just left them in place and use them primarily to secure the chairs during travel.
Off the top of my head, I think the total width was about 93" but not positive. In any case, there was room for the two Lazyboys with about 4-5" on each side and the Center Cabinet was custom made to fit. I think it is about 14" wide. The chairs were special order with the recliner handles on the inside next to the cabinet.
We moved the TV into another computer cabinet directly across from the chairs on a power lift so no more having to crane ones neck to see the TV.