I'm repeating myself, but even my street Camaro or Cuda have no factory engine parts, just aftermarket drag race parts. You aren't going to get Mopar or Ford to invest in a costly Pro-stock engine program-But- it means a great deal to the casual fan if the bodies are different on a Pro-stocker ! Make an incentive to run a mustang or Mopar body if you have to. That to me is the way you build interest in Pro-stock. All fuel funny cars (and TF) run a Mopar designed Hemi, so what's the big deal ? The outward appearance of a drag car is what the average fan on TV sees, and cares about , not the cylinder head design.