Hi , thanks for your nice words. I sent a couple articles to Extreme Modelling which goes into a bit more detail, hopefully Jose will print them! There's no secret to the weathering:
Paint with tamiya dark yellow
Wash with burnt umber oil paints
drybrush with testors sand & white oil paints
chips with humbrol enamels and black oil paints
dust is tamiya buff
pastel chalks for some staining.
The actual steps are pretty easy, but it does take practice to get the drybrushing right. I have been doing it this way for dozens of models and am happy with my results now.