MonsterZero,
Do as you wish.
As for me, I am always much more interested to find better a reallistic than an accurate finish, so I always follow my intuition painting my tanks. I have just given the base coat to my T-34 85 and I simply mixed colors until I got what I wanted. Yes, you are right, colors can change from one source to other, but even if you had the exact/authentic/accurate shade, it would change during weathering process later, so you also can start changing it since first painting step, instead of waiting for last, depending th final effect you want in your model.
My tank just now looks very light, but weathering techniques tend to dark base colors, plus I want to make a late war (Berlin, April 1945) T-34, so I imagine it should be light and dusty and no much original base color might be seen under such conditions, for example. Let me some time and I will post some pics soon. ok?
What are you planning to make to yours?
Enjoy modeling!
Lu