I attempted some weathering effects on the Land Raider this evening. For the edge wear-and-tear, I edge highlighted a near-pink color, then mixed orange, earth brown and black in a 1:1:2 ratio. Following that, I hit the edges with Mithril Silver. I used an assortments of Mig and Vallejo pigments on the tracks and in the usual areas, pushing the pigments on gently with a Q-tip following the initial brushing-on.
There's quite a bit more to do, and this was just a test, but I am liking the way it turned out so far.