Hello all, my first post on here has to do with exhaust stains. Anyone have experience using AK pigments for exhaust stains? I just bought the set which contains 4 pigments and the exhaust stain wash. On my previous model(my first ever), I used the wash only(only thing I had at the time), which looks ok, but it's more brown than black. I want smoky black trails. So what do I mix with the pigments to get that effect?