Since PC will do custom adjustments to their basic floor plans, I guess that makes it even harder to tell. The website's front page shows a chair instead of a cabinet behind the passenger seat for the 2552, taking up the extra foot length on that side. Is there a slide out pantry on the other side, by any chance? If so, that might be the other foot on the driver's side, probably indicating a 2552. Since you have a serial number and maybe can locate the vin number, perhaps call the factory tomorrow and they can look it up that way. Good luck!