The bumper sits on top of the raised parts. Secured at each wheel arch. I secured to the bumper bar with plastic grommets spacers and screws. I decided against any bottom fixings as you are guaranteed to ground at some point so having the bottom unfixed will allow a bit of flex and reduce chances of cracking. Normally the grill is only secured from the top but I fibre glassed a small bracket at the off side so it could be cable tied to the headlight/ bumper bar.