He says he has the PHS...The color would show up on the billing history under "color". What strikes me as doubting all claims is that after checking as many references to pistachio..no GM color could be found. Now here is where my cop mind takes over. Seller calls it pistachio. Seller would have to get this color name from SOMEWHERE documented to name it such.

The GM color chart for all green hues.. Scroll down for GM paint codes

If this truly is a "one off" I am sure Jim Mattison or JB would have hand written a few words on the PHS as to the rarity of this car.

Since the car color is purported to be a customer request (not an exec..) the cowl tag would read SPEC and not any other designation. My speculation is that if this is true, the cowl tag would be blank for the color code.

To solve the issue, either the cowl tag or the PHS would show this one off color. GM would not stamp a cowl plate with a Q code as an example (Verdoro Green) and paint it a non GM color without documenting the color change on the billing history within the spaces provided on the bottom left without a hand written addendum at time of billing.

Absent a clear pic of the cowl tag showing something (or nothing) or authentic GM notations and documentation, the sellers claims are without merit.

Could the person who requested the color have been special...had friends and connections at GM to have this pistachio paint done on the down low? Absolutely...but absent docs...I wouldn't bet on its authenticity.

Some exterior paints were special order and not in the dealer ordering...marigold yellow, pink mist, carnival red were some of them. If painted a one off...the cowl tag would show SPEC.

Please follow up with seller and request a pic of cowl tag and billing history.