Originally Posted by Watchmana7
If I'm not mistaken the original California Special Mustang, back in the 60's, had design differences and had emissions requirements that were different and were required for marketing in Calfornia.
I'm not aware of any emission changes to the GT/CS. They did sell the standard GT in California along with the GT/CS.
In 1968 California accounted for 20% of mustang sells. The Ford dealerships got together and request Ford to build them a special model that made the mustang standout from the rest.
As far as I'm aware the only difference between the GT/CS & the GT were purely cosmetic.
If you have any data stating otherwise, I'd love to read it.