thank you all for the suggestions!
I tried flat and polished aluminium... now I'm going to search some white alu from alclad. rag, when you say that you add grey... wich type (brand, I mean) of grey is?
I must admit that I'm surprised by my speed on this project, but also I have to say that I'm not working, on these days, so plenty of free time (well, almost) and that I skip on some details I don't fully understand, on specific request of the friend to whom it will go at the end..
so, on these conditions, it's easy!
bye bye, p.