Introducing JimL78...he wants to say Hi!

[Schonyenko2]

I have a theory on the black. While it may have been flattened, I tend not to think so. I think on an X66 that maybe the tailpan, and rockers were painted at the same time.
Remember that we're working with laquer. If you buff the primary color to a high gloss,(and you had to buff laquer to get it to shine) but you just sprayed the black on, and left it, no buff. It would have a dull sheen to it with out being flattened.
Over time as you waxed, and rubbed on it, it would actually get a higher luster.
I don't think you can really duplicate this with bc/cc. I think you'd need to use laquer.
Just my humble opinion, as someone who shot laquer back in the day, and have seen this effect.

Very cool car.