Ball postion between feet for each club changes but what I find most important is distance from stance to ball. If I want to play a fade I have the ball an inch or so closer to my stance to allow for more of an upright inside out swing plane. If I need a draw I will move the ball an inch or so further away from stance,(guessing on distances here,never measured them),to give me more of a flatter inside out plane. Done it this way for 40 years. Too old to change now!