I currently have 5 NOS painted GT350 Magnum 500's. (I will have to check the date codes.) Under close inspection with a magnifying glass, I have found very small traces of the black paint specks, the same color used on the recesses, very flat paint. Absolutely no shine. It appears to be over spray. This will also affect the over all appearance at a distance. I will try to take a picture and share.
The color code has been a mystery and has been brought up before. One issue that might make it hard. I bet there were variation in the paint batches from back in the day and that is why we can't agree on the exact receipt for color. There are several if not half a dozen or more. I have also had my painted Magnum 500 discounted for a color match. They could be different than the assembly line versions. However my set has not seen any exposure to solar radiations and have not be subject to weather of fading. They look really good to me. You can decide.
At SAAC 43, there were nearly half a dozen 66 GT350's with the painted Magnums. I will try to post those images later also.
Take care
Cory