replacing stringers
 

I have a 85 v20 I want to do repairs to floor my friend thinks that if we take the rubrail off that the entire top including the floor should lift off exposing the stringers so that I would not have to cut the floor where it meets the sides since that all appears to be one piece is this true

That is true. If you have the means to lift the top cap off you can expose the stringers and hull.