not a whole lot, all i have done is paint the arms that hold it and a few small details, i will do a few more before it goes in, ill try have a crack at it this week
You'd probably have to mix paint if you want to use Tamiya for it. It might be easier to use Vallejo, Lifecolor, Akan, etc. that already have matched RLM paints.
I have a set from Lifecolour which has the colours already matched as Pharmpony mentioned, i bought them for a project im preparing for, but i have get an airgun as lifecolour are more suited to airbrush