No worries.
Well, from what I remember the tank was *very* pale. It almost looked white in some cases. I'd send you a pic, but I don't have them with me at the moment. What's already been said above regards the colour is probably spot on.
Regards dust...it's *everywhere* in Cairo, and from what I remember in the Sinai if anything is moving around then it will get dusty, so the tracks should have a light dusting on them I'd say because it's not mud, so wouldn't cling. On our vehicles there was a light dusting. They still managed to kind of look clean at the same time. So I would say it would be the same with the tank.
There's always a difference between what your eyes see and camera captures, but I'd say this pic is pretty much spot on regards the shade: https://en.wikipedia.org/wiki/File:M4A4-AMX-13-latrun-2.jpg