Actually worked on the boat today :-)

I cut the marine plywood into 2"x5" pieces to be used to replace the rotten core. Trimmed up some of the rough edges of the old fiberglass cockpit floor and discovered that basically the entire core under the cockpit floor had failed. There was a section in the aft end of the cockpit, that had looked sound when I did the major tear out, but alas, it had de-laminated too, so out it came. I also laid up a fiberglass patch over a small dime-sized hole in the floor that developed at the aft end of the centerboard well when I was doing the tear out. So now it is on to sanding the remaining glue and core bits cleaning down with acetone and epoxy in a new core...