As I was lazy to update again, I post some longer-time update. Wings were weathered using oil paints (wash, dots etc), I started to work on engines. I modified valve mechanisms heavily to be more realistic using Taurus springs and some profiles. Rods will be added later to not to bend them during bulding process. Cylinders were weathered using AK stuff and oil paints. One engine has spark plugs installed and connected. Ignition cabling was scratched too.
M.