It is possible to modify a Chevelle fender to be used on a Beaumont. Here are a couple of pictures of the bracket that is spot welded in the front of the Beaumont fender. The bracket is the screw retainer for the grille extension and has an integral tab that uses a clip for the outside upper screw for the headlight door.

 The filler piece on the Chevelle fender needs to be removed by drilling the spot welds. Do not cut it out as you will need all of the metal that is remaining. The tab that is remaining needs to be folded back at 90 degrees. Sorry I didn't take pictures while I was modifying mine. Maybe Fred can help with that.