Cut-out fenders on dart?

Every modification that we make to our cars is a matter of personal taste, that's what separates the hot rod from just another restoration.
That being said, simply taking a sawz-all to the wheel well might look pretty hack.
It would be best if you were to form a new fender lip after making the cut. I remember seeing in a magazine many years ago where a guy used tubing welded to the edge of the opening to create a lip. The result looked pretty good in the pictures.
Another approach that I have seen on some customs, is to re-shape the rear wheel opening to match the front fender opening, perhaps using sections cut from a second set of fenders. Actually this is a long-winded way of saying; it's your car, build it to suit your vision.