Finally got it the colour I wanted, basically Brown with a very faint hint of Olive Green
Overall ABT 502 oil wash mix of Burnt Umber, Raw Sienna and Industrial Earth over a base coat of Vallejo Model Air Khaki Brown.
Got to decide now on the next weathering stage, thinking a smattering of medium Brown mud plus wear and tear marks.
Exhaust is done with light rust oil and pigment mix, Tracks are finished too with mud and tread wear.

Overall ABT 502 oil wash mix of Burnt Umber, Raw Sienna and Industrial Earth over a base coat of Vallejo Model Air Khaki Brown.
Got to decide now on the next weathering stage, thinking a smattering of medium Brown mud plus wear and tear marks.
Exhaust is done with light rust oil and pigment mix, Tracks are finished too with mud and tread wear.
