One minute sitting at the dinette was pure torture. We found a very comfortable seat for a pontoon boat (with storage) that is a bit shorter and about 3.5 inches lower than the bed portion of the dinette seat. It was a clearance seat and cost $250.
I removed the entire bed portion of the dinette, built a platform for the pontoon boat seat and trimmed the platform with commercial baseboard. Because the pontoon boat seat is deeper than the dinette seat, I moved the table mounting flanges out from the seat five inches and all is good.
We have never used either bed; it's just to two of us, so this is a perfect arrangement or our RVing life style.
The heat duct and seat belts are still functional. And now there's room for a round hassock between the dinette seat and the driver's seat.