Hey Wookie, good luck on your build!
Here is an official shot of the Blackbird at the Air & Space museum near my place of residence. It is quite a big bird in person. On the starboard engine you can see the different shades of black. You may want to try starting with a lightened flat black and post shade with very diluted straight black. Don't take my word for it, black birds still scare me and I've yet to do one, just a thought.
I just realized how many lights there are on this plane. More than any other in the hanger. The place is not especially highly lit, so I imagine if they didn't, it would just be a large dark object.
Go here to see the full res image:
http://airandspace.si.edu/explore-and-l ... 0Blackbird
