Hi there, I think I know the boat, in Moodys yard, was on board it 2 weeks ago.
My boat was simlar when I purchased it left in the sun not used.
My recommendations are as follows.
You need the boat ashore.
You need a professional polisher
Use oxalic acid to clean the hull off, diluted.
Use Farecla compound, I use G3
Use a "nano" polish, its fills in the microscopic holes so crap does not stick, Google it.
Then use you favorite wax polish.
I live up the road from Moodys if you want more detailed information on that model of boat and modifications.
Send me an email.
Odysseus
Bav 38