If we accept that the rear bumper of the Merc is in line with the 2nd newal post of the metal fencing (indicated by the top of the dark black post in the picture below to the left of the blue mark in the picture below), and after that comes the last newal post, by the green mark in the photo and then after that the keep left sign, which is by the red mark in the picture- I think we can prove this.
The distance from the edge of the box to a position not yet at the second Newal post (by the blue mark) where the mercs bumper is, is in excess of 4m so the Clio should fit and it simply stopped short, which isn't an offence.
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