Polishing the shaft
I usually take a small hammer and bash the barnacles to pieces, once the majority of them has been knocked off i scrape them with a putty knife. Once they have been completely knocked off with just small little rings left go at it with a scotch brite pad and polish that shaft. For the prop, i usually take a 90 degree air die grinder with a roto zip pad on it and go at it to produce a real nice finish, don't go to deep or you could remove to much material in some area and cause the prop to go out of balance. All the best, good luck with it all.