If you don’t mind drilling out the rivets and removing the braces from the fenders, you can get the braces pretty straight by just putting the bends in between the jaws of a vice and squeezing the bends out. The fenders can be rolled - look under services in the classifieds here on the CABE. I first give everything a good OA bath. I bring some luster back into braces by running them against a big brass brush on one of the arbors on my bench grinder. Learning which way the brush rotates and keeping the brace on the down side of the wheel takes some practice. If the brush catches an edge of the brace, it will grab the brace, bend it, and throw it across the room. If you have a good grip on the brace, your hand will go with the brace. Wear a face shield and heavy gloves. Then move to the polishing wheels. The inside of the braces are best tackled with a small wire wheel on your drill.