Isn't it supposed to be fun to own a Cobra
So "run what ya brung" and just have fun---what we drive today are generally far superior engineered cars than Shelby ever produced, suspensions are better, shocks are better, brakes are better and in some cases even the frames and bodies are better.
I wish my life was so un-complicated that I could get worked up over something so meaningless as only a 427so/co in a 427 body.
BFD--what's that give you bragging rights? Go for it--too anyone that sees you on the street, they most likely will admire your car whether you have a BB or SB and would give their first born for an opportunity to own one--consider your selves lucky indeed because few can afford to have one --just have fun with it
Life's to short to worry about rivet placement
