It is possible to knock the side pieces off a floor section then slide (pound) off one of the inner "segments" then put the floor section back together (you will probably need to cut down and smooth out the side pieces as well. Do some careful measuring to see which segment to remove (they vary in width).
I have done this before. Whatever you do, do not try to force a floor in that is too long, expecting the boat to "stretch." I've seen a couple boats damaged this way it caused a main seam where a number of joints overlap near the bow thrustboard to begin pulling apart and is a major PITA to fix!
Another proud member of the "Black Boat Mafia"