Thanks so much chaps. Sooooo... the squiggles. I used up all the available space on the inside of my Ki-84 wing part as a test mule for the squiggles. Started with very thin paint to thinner ratio and as low a pressure as I could get. I had to add more paint to get better results. I don't know where I ended up but I did have to increase the pressure to about 12 psi to get the spray to go consistently.
Even so, I couldn't get an extremely fine, pencil-thin line to spray consistently but ultimately decided to bite the bullet and start on the model. I started with the inside of one of the fins and, when satisfied, moved to the outside. Much courage was exercised in that decision! The green used to simulate RLM 81 or 83 was Tamiya XF-61 Dark Green. Looks a bit of a mess when close up but keep in mind the fin is only about 25mm (one inch) wide.
I then just continued on. After the paint ran out of the cup, I mixed up a new batch but had a hard time getting the same spray properties.
After this session, with paint left in the cup, I started on the much larger random waves on the wing tops. When I ran out of paint, I stopped to gather my breath.
So, all in all, I think achieving realistic tight squiggles to scale was beyond my current abilities and I may have been limited by my 0.2mm nozzle. I rather think, though, that I could get a little more out of my brush with more practice before blaming my equipment. That said, the overall effect is acceptable and I achieved what I wanted to - to stretch my capabilities and see how tight a pattern I could get.
Next, I'll finish the green off and then apply the rest of the insignias.