I wouldn't give up on it just yet 89S. Don't try to slop those panels in either. If they don't fit, they don't fit. So don't trash them doing a half ass job. Try to return them for refund, or sell them to someone else, or keep for another project.
This is why I don't think I'd ever buy panels. What you likely need to do is go to a wrecking yard, paticularly a pull a part or pick n pool, then cut a good section out of another burb that is about 3 or 4 inches bigger than you really need it, then you can fine tune your cuts at home, or cut out the bad metal, overlap your panel an inch or so and add spot welds. In fact where you are doing this, its not even going to show is it? In that wheel well? just run a solid bead and then hit it with rattle can undercoat so it don't rust again.