leave it be. in most cases, yes its good to take off what wont be hit by good lighting...(ie. lower branches, undergrowth and weak shoots) before you put it to flower. in your case, i'd leave it. you'll only be hurting what yeild you would have been given by cutting. maybe add a cfl or something to light up what isnt getting solid light...just my thoughts here, do what you will...thats how you learn man. trial and error.