There quite easy to get off, firstly look either end of the skirts inside the wheelarches there is 8 rivets to drill out, then underneath the car there is about 8 torx screws to take out per side, now take the small front section off first as this is covering up a bolt into the sill that holds the rear long section on it is possible to remove them without breaking the clips if you can get a trim tool behind the skirt but these do get brittle over time so they will probably snap, you will notice there is 2 types of clip on the skirts only 1 type is still available from ford now the part number is 1667244 and you can use these on the full skirt when you come to refit them.