I used Tamiya XF-70 Dark Green 2(IJN) with alot of white added. But after weathering it was very different green from what I started out with.This a photo before the weathering was finished.
As for color, I'm not an expert, but British tanks were bronze green. It's a greener than US olive drab and even the British version of OD used in Europe. I know Humbrol makes (made?) a bronze green. I don't recall the number at the moment. You'll want to lighten it a bit with white or light grey for a 1/48th scale model.