Just saw this car pull into the pit lane during free training and thought to myself how nice that would look in...oh wait, you already done it! Awesome man, thanks!
Thank you. Inside the rar file you downloaded are two folders, open the one with the resolution you want (e.g. 4096=4K) and extract the folder inside (called "2017_larbre_lemans_50") into the "skins" folder of the Corvette C7R (.../steam/steamapps/common/assettocorsa/content/cars/ks_corvette_c7r/skins/). Done :)