Vijay Singh is a great swing to model because he has great freedom through his swing, allowing him to get a great hip and shoulder turn and unload on his downswing through to an extended finish position
There is a really small difference in stance widths, with your driver your shoulders should line up with the outside of your shoes while with your pitching wedge they should line up with the inside of your shoes
Practice your entire swing in super slow motion, this will allow your mind to focus on the correct muscle movements needed instead of trying to make your brain work on the correct movement while you are swinging, just do it don't think it