I used hu75 with my Achilles and nobody complained, but dark green 30 (or 149) looks more like the color on the Tamiya box.
Here's an in-progress pic of my carrier.
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The basic construction is done. I haven't cemented the front armour plates yet, to make painting easier. I'm doing the model with Eduard PE and Modelkasten tracks. There quite tiny and there's about 400 of them....
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The most time-consuming part was to get them of the sprue and clean up, a job that took about four evenings. Cutting had to be planned carefully because the track pieces are connedted to the sprue by 3 connectors. These things break very easily, so I clipped them with straight-cutting clippers like this: first cut the single connector on each track piece, then cut off the sprue around the first piece, cut the double connector to get one piece off and repeat three hundred and ninetynine times! :-)
But these are worth the money (just as much as the tamiya it itself
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But back to the subject, what's the right humbroll color for the british dark green?