I have a T6 Caravelle, and am looking at doing the same or at least something similar.
After visiting busfest last week about the only thing I came away with was the idea that a rear pull out drawer / sink stove top combo would firstly provide the board required for the bed to rock n roll….. provide brewing up fascility etc etc.
in answer to your seating issue, having previously owned a T5 Calli Beach, the multi flex board has a drop down section 4 -6 inches maybe ? It flips up once the bed is deploy ed ? It also slides back and forth in the rails. The middle row seats do fit with the board in situ at the rear, bench seat up against that and then the 2 individual seats facing either way.
