I bought one with the family extenston. I was going to put it in over the winter, but I ran out of time. Needed a bit more fabrication than I had the time for. From what I could tell with the pieces laying in the general location, it looked like plenty of room for the passengers and the seat fold-up. But thats just a guess. Come summertime, I will have everything completed, but you may not want to wait that long for an answer. Hope someone else can chime in.