[Stentor]

Are you looking for a fiberglass car or aluminum (as this will impact answers to your questions)?

As Power Surge mentioned, the wait time for production of CSX4000 cars has dropped dramatically. And there are rollers that are immediately available through dealers.

Regarding a Shelby engine--you can get a Shelby FE aluminum block through numerous sources (as well as other Shelby engine components), and you can have a reputable engine builder put together the Shelby engine for you (e.g., Keith Craft, Gessford, Barry R, Roush), or you can have Shelby (Carroll Shelby Enterprises) build a complete engine for you (for which you will pay a premium, and likely have less HP and TQ than if you had the aforementioned guys build you a motor).

Good luck.