I had mine done because I think it looks cool. No different than all the other things we spend our money on for the sake of satisfying our own preferences and sensibilities. This engine (aluminum 535) is going in my 70 pro-touring formula.
Certainly not intended to fool anyone...folks who know enough to care also will know it's not the real deal. Used a real one on top for mock up and building headers...can see many differences.
