Here is my theory: it was all about marketing. He was very motivated in selling these cars so he had to make them "hot". This would explain the four colors that I would call high impact: Hugger Orange, Daytona Yellow, Rally Green, and Lemans Blue. These colors would attract more attention from the younger buyers and thus probably sell more cars. Now for the other two colors it seems it would also make for another marketing idea. Look at the other brands of cars being sold in 69, including GM, and the colors offered. It seems that golds and dk. greens were very popular in the late 60's and may have led to him offering these colors also. I Don't know why he did not offer at least Garnet Red or Dover White, unless he felt these colors should be on the Novas and Chevelles only. Why didn't he offer Daytona Yellow or Monaco (Hugger) Orange on the Chevelles or Novas in 69? Look at Pontiac's Judge, orginally they were only going to be offered in Carousel Red (Monaco Orange) and then Pontiac made a change and offered the Judge in any GTO color including Fathom Green, which was a very popular color on the GTO & Judge. Now for the Turbo Z's I do not know what colors he offered but it would have probably been along the same lines as the three cars I have seen were either red, white, or blue: all very common colors in the early 80's. Thanks for the time as this is just a thought............Rat Pack...........