Today I attempted, successfully, to install the first stringer on the port side. I used a small Electrolux Steamer (thanks to Mark Attard) to apply a little steam to the stringer which I had placed in the 75mm PVC tube you can see on the floor. The steam certainly made the pine stringer more pliable.
In place of clamps in some cases I used electrical cable to pull the stringer into the frame.
I have primed and painted the underfloor area as it is much easier now than after the stringers are in place. I will apply the final coat before the floor goes down.
I used the steamer by hand to apply a little more moister before srewing and glueing.
I have inserted two 25mm electrical conduits between the front floor area and cockpit to drain any splash water to the rear.