Tony Polson wrote:

red = live

NO, NO, NO. RED was EARTH - definitely. Obvious danger lurks...
Now you see why harmonisation of colours was such a good idea.

black = neutral

Black is live, I think.

but is the grey wire really the earth?

Grey for neutral

Definitive advice will be very much appreciated!

I'm not 100% sure about the last two, but RED IS DEFINITELY EARTH.

--
Andy