[computerworks]

Karl...
Briefly, they are Cobras built in this generation (early 90's) by Shelby (and McCluskey) using unsold Statements of Origin from the original Comp Car run back in 1965 ( in the CSX30xx sequence). They were offered for sale, with much fanfare, at $500k each; several were sold.
A minor scandal erupted over whether the chassis parts were left-overs or replicas, involving SA, AC and the Calif DMV.
This resulted in a settlement with the state of Calif, wherein the MSO indicates "cannot be registered for street use in Calif."

From where I sit, they are custom-built, very-faithful replicas, signed and built by CS and carrying very special CSX30xx numbers.

...but they ain't originals.