We have an Andy Mile boat (4287) at our club which carries 3kg of correctors. I'm surprised that yours is registered as overweight as they were a quality product in their day and should all have come out the same weight. My first step would be to get your boat checked on some scales that are known to be accurate as a first step.
My boat is 70 kg with no correctors on the rya certificate, so it's on weight officially. My boat is in for a paint and tidy next month and I wanted to get some weight off and correctors in at the same time- largely to reduce any gain over the last 20 years and also to counter the proposed reduction in all up weight if its voted through.
I would agree Godfrey ,that Andy Miles made a superb boat and that most have correctors. I will own up to checking very carefully for any filled screw holes on the centreboard case where correctors may have been fitted in the past. No holes!
I am going to get the boat weighed next month.
Still open to any more options to reduce weight if the scales agree with the certificates!