Your ball position for ALL shots off of grass, including your driver should be 2″ inside your left heel for right-handed golfers.

It is a myth, that you should change your ball position for each club, the only thing that should change in your set-up is the width of your stance.

For instance, with your pitching wedge-your stance should be narrower than shoulder width.  Therefore it will appear that the ball is in the middle of your stance.

As you get to your longer clubs, you should widen your stance, by moving your right foot further away from your left.  With a 7-iron, the outsides of your feet should be shoulder width.

With your driver the insides of your feet should be shoulder width.  Once again, the ball still remains 2″ inside of your left heel.  So it may appear that your ball is more forward in your stance, but in actuality your ball position has remained the same.