Sir Goose,
I fully agree woth the previous comments.
I just like to add something, though.
The rivets and recesses:
This is exactly what happens with a whitewash, the white is more visible in areas you canīt rub. So Iīd add very dark brown wash around the rivets and recesses. After that you only need some drybrushing with white to bring those rivets up again. This is what I just did with my winterwashed BT-7.
I found an even easier way of doing this. If you know from the beginning that you are going to make a whitewash camo, prime your vehicle matt black. Then apply the normal camo pattern. Then comes the white.
Now when you wish to weather the vehicle, you can control the white/dark balance simply by rubbing the surface harder. If you want dark panel lines, weld seams, deep scratches, just apply some thinner and rub with a cocktail stick. You can also go around rivets with the stick. No need for dark washes and the principle will be the same as the natural wear of the vehicle. The more you scratch, the darker it gets!
Good job on the Wirbelwind!
Toni