The wings are bolted on.
You'll need to remove the front bumper, headlamp, wiper arm, scuttle trim and side sill trim to get to all the bolts. Be careful with the side sill trim, you need to remove the clips from underneath and the screws at either end and then slide (possibly tap with the palm of you hand) the side sill towards the back of the car to remove it. If you try and pull it off, you'll be wanting a new side sill trim as well as a wing. Once the sill trim is off, twist the white clips in the sill to remove them and then clip them back into the trim, the clips should have black rubber/fibre seals on them, don't lose these, they help stop the sill trim from rattling. The sill trim will just clip back on when refitting, no sliding involved.