Oh no, that's why I said, "if the body is not,...warped". There's nothing you can do to square up the body other than cut that corner out, and add the amount needed to that wheel well, to be the same on all four corners.
The point I made was how to square the wheels, in the wheel well. Even on mine, after lowering the rear of the car with different coil overs and replacing the heim joints, I think the ride height now is great for me. But, if you see mine in broad side photo, you'll see that my Ford 9" looks too far back, I need to shorten my four bars, to bring the rear end forward apx. 1/2" to 3/4".
I would have to take a different angle shot than this pic to show what I mean but, if you look close, you may see how I need to more it forward, just a little.