That car is sweet, I would not modify the wheel lip. I have seen warped qtr panels and long faces after such an act.
Taking a baseball bat to your car.... PLEASE re-read that again carefully. Taking a baseball bat to your car.
I would highly suggest you use a tool that allows a controlled result. These cars did not live this long for us to take a short cut that could be very risky. I opted to relocte springs and use custom backspace etc in my Cuda.
Looks like you have about a 295 under there now what is the reason you are wanting to do this? Do they rub?