He sandwiched the hull side in 1x2s, leaving room for fingertips above the deck. I also like the added straps holding down the bowsprit. This is the aft one just to the left of the rail end. The other was a couple feet forward.
I like the slat seats design for at least two reasons--dryer when water finds its way into the cockpit, and a bit comfier on the backside. That, and the extra leg room.
"Place seat here." This is a view of the cabin bulkhead end on the starboard side.
Seat installed on the port side, viewing the aft end.
Aft end support on the starboard side.
Notice the lip on the front edge (left).
I plan to fully enclose both the lazarette and the seat backs, so I will probably build my seats like this: