M37 Air Force Groom Lake markings?

[Richard/SIA]

A friend has an Air Force M37 he wants to paint in the original blue.
Groom Lake, AKA "Area 51", also AKA as The Worst Kept Secret in Nevada is kind of humorous to a lot of us.

Just for fun he would like to mark his M37 as a Groom lake vehicle.
I'm sure they stopped using them a long time ago, probably have Hummers now.
Might get some comment in the parades with it, if he can get the marks reasonably close.

Anyone have a clue or two for what might at least appear to be correct?

[ng19delta]

As I recall, they used invisible paint for those markings.