I bought a roof rack for my recently purchased LR3. I'm trying to instal them myself, but have ran into problem. There are small plastic button like screws (I think they're screws) along the factory roof where the roof rack will be placed. I can't get them off without breaking them, and I don't want to break them if I need them again. The instructions don't speak to these screws. It looks like once I install the rack I have to cut the old insert and put half of it back on, so I don't want to damage it by bending the hell out of it trying to pop the screws free. Anyone know what to do???