American Car Craft Dodge Viper Side Hood Vent Grilles Billet Style with Viper Head 2Pc Polished 1992-2002 - Manual (Page 4)

bend the grille into the curved shape needed to match the cars fender.
Once bent to shape you should be able to hold the part up to the fender
and it will automatically conform to the curved shape of the fender (without
tape holding it in place).
5. Position the grille, then peel the red release liner from the back of the grille.
6. Carefully reposition the grille over the hole you just made and set the
grille so that it sticks right into the groove. If done properly the
grille should stay in position by itself.