carb settings

Anyone tell me the jet sizes on a stock 71 cb350? I need to get the carbs cleaned as it's not running properly. The bike sat in a garage unused since 1974. I'm figuring on just replacing the jets in it. Also any settings someone may recommend being at 2700ft elevation? My 2strokes are real finicky with altitude changes but I'm not sure about 4strokes being so picky. Thanks in advance