How the paint a Russian APC/BTR-40 drive-train?

[Johan]

Autumn Greetings from Sweden,

Hope you can help me with an idea of how to paint the drive-train, engine gearbox, axes, springs on a Russian BTR-40.

I have seen reference pictures of other Russian APC's where everything but the hull was painted black.

Would very much appreciate your input on this

Very Best Regards
Johan