Kris Jenner's Great Gatsby themed 60th is already on the road to being an epic bash ... crews are hauling in period cars to make the night authentic and awesome.
Check out the pics we got of a trailer hauling two old school mobiles -- a Caddy and a Rolls -- hours before Friday night's party.
TMZ broke the story ... Kris' kids are going all out, spending $2 million. For 300 guests, that comes to $6,666 a head. What the hell?