Riveted F-1224-L & -R baggage floors to center section assembly (page 21-02, step 2). Was able to use a short cupped die (from Cleavland Tools) on the manufactured head. Denise provided finger clamping pressure on the edges of the floor flange for each rivet. Finished the night by clecoing the baggage ribs to the F-1204D aft bulkhead and baggage floors.