I've done it years ago. In my case the floor was soft, but stringers were good. The size of the project depends on what you find when you remove the old floor. If you have to do stringers it becomes a much bigger job. Best advice I can give you is to try to retain the old floor pieces as templates if you can. Should make replacement much easier. Also, replace any waterlogged foam you find under the floor. The reduction in weight should help the boat's performance too.

SS

"To be glad of life because it gives you a chance to love and to work and to play and to look up at the stars. To be satisfied with your possessions but not content with yourself until you have made the best of them."
-Henry Van Dyke