Some food for thought....
U.S. Cartool in Raleigh charges around $15K for their "Body in white" program which gives you exactly what you describe...a rust-free shell in primer, done on a rotisserie . Yes, shell only, no fenders, doors, etc. Paint and assembly NOT included. From what I hear, they have a waiting list a couple years long.
You guys with the rust-free cars for $2k, please forward that info to me so I can buy them all and put big blocks in them.