Funny you should ask.
On the back cover of my first book, I have a color picture of the big unveiling event that was on Feb 15th, 1968, at the Century Hotel in Los Angeles (near Beverly Hills).
On that night, ALL the Los Angeles dealers signed up to get some cars-each. When they sold those cars, they got more (GT/CS). The more they sold--the more they got. They set a FORD wholesale record with the most cars ever signed up (by dealers) for in one day!
There weren't as many Northern California FORD dealers with the GT/CS, but just about every one in California got at least one car for sale. It was a promotion--so it was sold in that way; as opposed to getting some "390 cars", or some with this or that color, etc... The whole country got the "Sprint" package for the spring of '68, and California got it's own--the GT/CS!!!
I do remember that some very early cars were sold in Southern Oregon, as that area, up to Medford in part of the 72 DSO.
Colby Ford in L.A. sold a ton of the CS cars. I have full-page newspaper ads of that period, and classifieds from Ford Dealers saying: "Now in Stock" The All-New GT-California Special"......come on down and see it!!
It was a very big thing in Los Angeles--they even had a big billboard on Sunset Boulevard to promote it with a big red CS on it! How cool, huh??
Paul.