Yep, ordered our 337 with a king--did not like it. Difficult to make up bed; had to crawl into bed from the end.
Cut the plywood top down to queen size, it overlaps the base of the bed so no problems cutting top. Then put self-stick, cheap vinyl tile on plywood. Easier to slide mattress around if needed. Got a foam mattress from Sam's and cut up the cheap, king mattress and put in dumpster (could not give it to any charity, they did not want it).