Guys, the mat colour, even black ALWAYS has weathering effect. You can notice the same on Blackbird, its not only black, but mix of different tone of black and dark grey. Its possible to achive here by PBR textures but thanks to different coulor on texture too. Then the model will look natural.
Few examples IRL if someone thinks that it has to be black only:
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(the last one is from museum from sure and effect is too strong, however it isnt using outside now so it’s good as well to see some external effect).
This is too strong, but real picture too (check the place behind the valve for aerial refueling)
This is interesting and good effect on the kit model:
Personally I dont like factory fresh and never used plane, I hope some of those effects will be present too.
But according me the author will do it due what I saw what he did in the cockpit 
and the last sentence “These screens don’t have any textures, its just the raw model and decals”, so he knows about it and we will get a very high quality product (which I have no doubt from what I see) 
Thank You!