To allow either the front or the rear panels to be removed, you must remove the sideskirts.

You only need a pair of pliers or wire strippers to remove the skirts.

Using the tool, carefully pull out the pin from the plastic rivets.

Pop the remainder of the plastic rivets out.

Reach under the car and unclip, by pulling down, the clips on the floor pan.

You need to 'untuck' the front wheel arch lining from behind the skirt.

Pull out the back edge of the skirt. There are two clips securing it into the trid.

Now hold the skirt securely and slide towards the rear of the car about 3/4".

The skirt should now be free.

To refit, you have two options. You can line up the white lugs so they are all horizontal, or remove them and place them into the skirt for refit.

We found it easier to line them up and leave them in place; this way we knew the depth was correct against the trid.

Carefully line up the clips against the slides on the back of the skirt.

You can use your knee to give extra support to the skirt(!), and slide it back into place.
Clip in the rear and relocate the front wheel arch lining inside the skirt (reverse of removal).
Remember to secure the clips to the floor pan too.