One of the problems that create this inside out swing which starts the ball to the right and causes those push shots is what happens right after impact. A lot of players make a very good backswing, make a good shift, they will clear at the right time, but then they will hang back. The right side will hang back and make the club extend outward and away from you, causing the path of the swing to be to the right and create that push shot. What you would like to have happen is on the downswing shift to the left foot; you rotate your hips but keep the right side going. The right side works like a door to close the club and bring the club back around to the left so that when you finish the right side should be past the left and all the way over your left foot. A wonderful drill for this is to take your set up and place a club down by your left toe, with the butt of the club at your toe and perpendicular to your target line. Then get yourself an umbrella and stick it in the ground just on the outside of the ball, even with where your left toe would be which is represented by the club on the ground. Then remove the club and what I would like you to do would be to hit shots where you go back to your heel, shift to the left foot, rotate and then try to finish with your right shoulder in front of the umbrella. This will bring the club back down the line, back around to the left and will help you finish fixing that push to the right.