I started off by priming the entire model with Army Painter Plate Mail. It actually gave fantastic coverage and didn't obscure any details despite some of the things I've read about the product.
From here, I hit the areas I wanted to be black with Vallejo Black game colour. It gave really crappy coverage and needed a couple coats. Even then, areas just flaked off. I'm not sure if this is just cos it doesn't like the metallic primer but all the GW colours were fine. Going to have to pick up another black to see if it is the Vallejo that is the problem.
Anyway, I used a GW black wash to shade the metal areas. I used up to 4 layers on some areas and it came out really nice.
I then blocked in all the base colours using the foundation range from GW. The red took 2 layers of mechrite red foundation and about 8 layers of thinned blood red to get a nice flat colour.
Here is the model with all the base layers done. I have decided what to do with the missiles on the front yet so these still need to be done. Still a fair way to go but it's starting to take shape :-)
(Some parts need a bit of tidying up but ill worry about that after I've shaded).