Looks like a good start. Good looking pup.
Stringers look to be in great shape. Drill a little hole a 1/2" above the hull in the side of the inward side of the stringer, in the back of the boat, and see if water comes out of either of them. Be careful not to got through the hull bottom.Did you want a ledge to set the new floor on? DOH!
You can also glue a 1x1 ledger around the perimeter. You have plenty of vertical space on the liner sides to do that. Are you planning on raising the floor?
As long as you seal the wood real well you should be fine.