Look at the bottom of the guards on the bracket where the bolt goes...each is marked R & L ...Just make sure they are on the correct side.Yes, they fit like crap. I have them on my 68..all GM pieces. They almost fit the contour of the bumper, but not anywhere near as well as you would like them to. I laid out where they go with masking tape on both sides of the guards on the bumper. Then start to tighten the bottom bolts to the valance...As you tighten the top brackets it will "draw" the guard into the bumper...putting two permanent grooves in the bumper.Vey crude and a one shot deal..Take your time and good luck..
Steve