Though I’m not really a fan of pre-mixed washes, I decided to use a Mig one intended for dark yellow on this model. I did some tests first, on the underside of the load bed and the inside of the chassis below it because those will be largely out of sight, and I concluded that this Mig wash needs to be thinned about 1:1 with water if you’re going to use it as a simple, all-over wash. So I did, by putting some on the model with my brush, then dipping it in water to add about the same amount of that and smearing it out.
On the vertical surfaces I used a large, wide brush to create vertical strokes after the wash had dried a it but was still wet. This went reasonably well, but the wash changes its intensity to some degree as it dries, I found afterward. It also turns the model darker, as I had expected, but what I hadn’t anticipated wad that it makes it much more matt as well.
Anyway, to try and lighten the model’s shade a bit again, I drybrushed the dark yellow parts with the Mr. Hobby paint I had used for the main coat. After that, I also drybrushed those same parts with an old Rackham colour called Parchment Yellow, both to lighten the model and highlight the details:
You may also spot that I painted part of the upper surface of the front of the cab with dark yellow, because I suddenly realised I had forgotten that the windshield would have been on the vehicle when it was sprayed. So before the wash, I taped off the front half and painted the rear dark yellow with a brush.