Re: 1991 Sea Ray 200 BR
It isn't technically difficult but is time consuming and hard work. You will need a grinder, saw and other tools to remove the old. What you need to replace the old depends on the size of boat, type of resin you are going to use, how much decking needs replacing etc. But basically you will need resin, matt, mixing pots and sticks, PPE, acetone, chip brushes etc.
However, rot tends to happen from the bottom up so if the deck is rotten I would check the stringers, bulkheads and transom very carefully with core samples. There is loads of information on this subject on many threads in this forum.