Thanks for all the replies!
@supergamerfreak: As ctaylor33 said, I think 3 BTS are the play. Also, I think 3 Junk Arms is optimal number.
@ctaylor33: I used to play Gyarados with heavy SP tech - 1-1 Luxray, 2 Crobat G, 4 Poke Turn and after that I figured that Crobats never did much good in...