They would probably get it wrong. What were those horrible retro cars of the 70's, Excelsiors? All the proportions were wrong.
Old car bodies used to sit on top of the frame rails. Hot rodders would "channel" them to lower the body between the rails. Now, all new cars are effectively channeled in their unibodies.
You'd probably have to build the replica car on a truck chassis to get it to look right at all, and it probably wouldn't pass any of the regulations.
Best scenario, save an old car.
Do you mean the Excaliber?