Re: removing previous boat names
My last Boston Whaler was a Striper 15 and had a long name in 12' high letters painted on each side.
I carefully and successfully removed it with #120 wet paper on a rubber block, but then was left with a big bright spot in the gel in the middle of aged gelcoat. I finally wet sanded the whole boat with #400 wet paper, then polished it. Came out like new.
If you do that, be really careful not to sand through the gelcoat. Some makers put it on pretty thin.