on mine, the original splitter is cut off so that its not hanging so low
the middle part of the splitter is just screwed on to the plastic under the bumper
and as each end of the splitter didnt have anywhere to screw too, a bit of bodgering didnt go a miss
i bonded a little block of wood to the inside of the bumper and screwed the splitter to this. theres a guide knocking about which basically says to do it this way if your sticking it to the original splitter as theres no where else for it to screw to