Jumping ahead to start thinking about access panel for the steps. Had already done some figuring of these so it was just a mattter of final locating the opening and cutting it. Realized that the stiffener would cross the access panel doubler and be a bit awkward. Solved that issue by using a filler plate below the stiffener. Trimmed the doubler plate to clear the filler plate and not conflict with the other primary rivets. Right side pretty much figured out. Need to mirror over for the left side. Won't assemble until I get to this step later. 8/20: got the left side knocked out today. Used the right floor as a template for drilling to make a perfect mirrored pair. Cut out with dremel. Results so so. It will all covered up anyways. 10/8: This was all wrong. Ordered new baggage floors and will redo.