The notable feature on the portside aft is that the shell plate held together as a single unit. It splays out with an easy roll. Ken Marschall paints it as rolling out and touching the bottom on the forward edge. I think it hangs just above the mud, but I need more evidence.

C-deck featured the 3rd class smoke room B, and the general room (or lounge) A. Note how C-deck bends down and lays on D-deck. The opening below the A in the photo is the 3rd class stairwell going down to G-deck.

The wall marked C is the forward section of the 3rd class smoke room. It hangs at a more pronounced angle than the rest of the shell plate. These ribs are on 27" (68.5cm) spacing. Forward of the smoke room and poop deck, the ribs are 3 feet on center (91cm). The actual ribs are a little more irregular and bent than seen on the model.

The wall just to the right of E-deck in the photo is the water tight bulkhead. Implosion damage at that point left a notch in D-deck with joists and a strip of deck plating hanging down. D&E decks exposed here were 2nd class cabins. D-deck on top was cleanly swept in the sinking and only a few fragments of wall mountings to the cabins can still be seen.