It's hard to imagine a motor pool wanting to deal with a 6-pack setup, not to mention any other "special setups" performed by "NASCAR shops". I dunno, I'd want some proof of that kind of stuff happening. Lots of stories about "special order" cars being more than what they really were seem to run rampant in any category of classic car.
BTW can someone tell me why anyone would want a white steering wheel? Was it to keep it from getting burning hot in the sun in southern climates? Trying to keep such a thing clean, or even clean-looking, would be impossible after a few thousand miles!