So ive now managed finally to pull the frame off the pylons.
I found that there was some sort of blockage in the air vent so have removed the both plugs in all four pylons... suffice to say that there was a fair bit of water in there !
I can see another foam plug lower in the pylon but think i would have major difficulty in getting at it so have decided to leave it. Have left it for a few days and now am thi thinking of replacing the foam plugs with the "noodle" spoken of in other posts. Was hopeful that Matt Miller may be able to advise if there was anything to watch out for when doing this repair. Will will be glueing the frame together when we put the boat back together so this could be the last time ( for a long time at least) that the inside of the pylons see the light of day.