While I am waiting for the canopy mask to arrive in the mail, I decided I could get some work done on the underside of the plane. The color of choice here is Neutral Gray from Tamiya. I planned to apply the base color, then do some highlighting with white added to the base color, followed by some random darkened gray. In the photos I have of this plane, you really can't see much of the underside. I would expect the paint to be worn and a little splotchy, but probably not faded.

The base coat went on well, then I applied the lightened gray in a random pattern. I masked the ailerons using post-it-notes and applied the lightened color. For the darkened color, I wanted to try using an AK Stencil to apply a very random pattern. I haven't used a stencil before, but I like it. After that was done, the underside looked like a tiger with dark spots. I sprayed a very thin (basically a wash) coat over the entire underside to unify the colors.

Overall, I am only semi-happy with the results. I didn't have enough difference between the tones I was using, so when I applied the last unifying application of the base color it basically take away all of the contrast. I plan to put the plane aside for the rest of the day and decide tomorrow if I need to do some more work on the underside. There will still be a lot of work with artist oil colors, so I will need to allow for the later work to come. I painted one panel with a slightly darker gray to suggest a panel replacement. We'll see how it goes. When you look at the photos, they were taken under different lighting that make the colors look vastly different.

Everyone stay safe. Cheers.

8 attached images. Click to enlarge.

Even after the base coat it still looks ok to me, George @gblair
Slightly less contrast, but still visible.
Indeed an interesting technique with nice results.

Thanks, Spiros (@fiveten), John (@johnb), and @lis. I may do some freehand work with some lighter gray to build up some contrast and panel lines. I always let the model sit for a while so I can look at the work with fresh eyes.

Thanks for the suggestion, @lis. I have tried starting with a black primer, and I like it for some colors but not others. I have also tried starting with a light surface, then using black on the panel lines, then use the base camo color in thin coats, allowing the shading to show through. I found it to be a little hard to control. I usually have the sense to stop with the thin coats before I completely cancel out the previous work, but this time I went a little too far. I can usually save the effect with a little more contrast or by using artist oils to tint the previous colors. I think I was also surprised by how dark the Neutral Gray dried...I had expected something a little lighter. Cheers.

George,
Very impressive ! I am always amazed at how some people have the talent to do this type of painting, yourself included in this group. Myself, I have tried it twice. The first time I was successful, and it turned out looking good on my Heinkel 111 that was part of the Kasserine Pass GB that we had about 3 years ago. It must have been beginners luck.

So I tried it again and failed miserably. My “spare” time for building models is not what it used to be, so I have not made any attempt to try it out again. I’m not saying that I won’t however, sometime in the future.

Thanks, John (@johnb) and Louis (@lgardner). I have to admit that I really don't have much of a plan when I do these sort of things. I just keep spraying until I get something acceptable, or until the paint is so heavy on the model that you can't see the panel lines. Sometimes it works, and sometimes not so much. Cheers.

Looks great, my friend @gblair!
I pay kudos to your systematic approach, the result being subtle but noticeable, Just Right, might I say.
Looking forward to your progress!