If I had to grind the heads on a bolt to make it work I would send it and the rest of them out to be plated. I would not paint them and I would not take a chance on not having any rust protection. As for the rubber disc that goes over the washer/nut all, every e9 that I have dismantled had them. Alan's is no exception. If they were missing then someone removed and didn't replace them or the car was so old and crusty that they rotted off.