a very nice job but.......
in this country anybody with those types of cars ships them in 1 of 2 kinds of large trailers
(because of the value and rarity of the cars like that ) either a solid sided (metal) trailer or a trailer like what you have done with canvas curtains on it.
so to futher add to the time you spent on this VERY NICE trailer you may want to add the nessary bars etc to it and maybe simulate some canvas curtains too