It's going to be a real shame to paint that! Looks marvellous as it is.
Thanks, and totally agree about the look of it unpainted! Someone said the same thing on another forum too, where I put some pics. It's the black and brass thing, isn't it? I have to paint it though, otherwise it would always look unfinished to me.
I'll take great care not to use thick coat anywhere and obscure detail - those walkways on top of the tank, for instance: they'll be a challenge!