NICE !
Even original vinyl !
My transom had rot where the speedo tube came out and soaked down and over to drain hole.
It also had the entire left side rotted behind floatation foam box on left side.
Water must have gotten behind wood where the fiberglass transom flairs out, as the foam was dry ..
My stringer was fine, except where it V's for bilge bowel, with unsealed drain holes.
Jason (Red 1976 CV16) and myself and a few other CV's have crack in hull in lowest chine near stern of boat.
You might want to add some extra fiberglass in this area while you have the floor removed.