mine were a bit more expensive than yours, and made of carbon fiber... you may have just picked a bad egg. the edge that wraps into your wheel well should be tapped just like the fender liner or a front lip would be, and for the other side of the valence, should be tapped where it tucks into the bumper, i´ll post pictures up later to show you exactly what i did. mine line up rather well, and are snug. you may have a problem getting yours to do the same. goodluck