I'm gradually sealing the deck leaks on my Carter 33, I've already sorted the Chain Plates and Roof Light.

I suspect that I've water entering from the interface between the Mast Deck Collar and deck (keel stepped mast). I've a couple of questions that I'm hoping somebody with some experience of this installation maybe able to help with.

1) I trust this installation doesn't support the mast in anyway and its undoing, lifting and resealing to the deck will not effect the mast.
2) What would the best sealant be, Butyle tape or some sort of gunk?
3) The rubber boot looks to be in good order, any advice on its removal or refitting?
3) Are there any other pitfalls I should be aware of?

Thanks in advance.