Go to a model shop, get a Humbrol chip/conversion chart, and see for yourself just how rubbish the Revell colour range actually is for anything not painted in German RAL tones. You're not getting much help here because... 1) This is an official Humbrol/Airfix/Hornby forum, and promoting other manufacturers is understandably against site rules. 2) At least one of the cited Humbrol tones will be a mix of 3 Revell tones. 3) Pretty much no-one, not even WW1 experts, knows for sure what colour(s) a British Mk1 tank was originally painted in, although we do think they were repainted in H27 grey.