I’d be tempted to get a copy or two of A&A Pacific 1999 version. The Japanese pieces were a bright red colour.
If painting, I use a spray can but airbrush is same principle, secure the piece to a backing. I use double sided tape to keep the figure/unit from moving.
Next, and this is key to any painting, use light dustings when spraying. It will take longer and more coats but the result is far better. It also allows the paint to dry properly.
I line units up on a strip, say 6"-8" long. I spray down and back up the strip catching areas between the units first. This allows me to judge how much paint is needed when spraying the most visible areas.
I use more paint than most, probably, but nothing worse than a unit where all detail is gone from blobs of paint.