I'm changing out the UCA shaft bolts that hold the shaft to the car. I bought grade 8 bolts and nuts. My question to those of you that have done this, what did you use for nuts? A standard nut and a lock washer, or other? The stock nuts have what looks like an integral washer on the nut, but I'm not sure what they used at the factory to keep them from backing out. Lowe's didn't have a nut that resembled the factory nut, at least not in grade 8 hardware. Any suggestions?