Hi motoringman,
the places I offer are 5*7 metres - but I doubt anyone will care if your motorhome is 0.5 m longer, places are not marked so precisely anyway. Last year I saw Motorhomes the size of travel coaches on Bleu Nord, but I don't know if there's a new rule about it this year, may be en e-mail enquiry to
ticket@lemans.org can clarify this.
Best
Werner