How green is my roof ?

Cracking on with the Class 14, I'm having a few problems working out the livery. For example, most of the locos had a roof the same colour as the body. Except the one I have photos of, a preserved example, which has a grey one.

There is also an interesting variation of black bits and green bits. This differs between machines too.

Of course, you will be telling me to go and get a photo of a single loco and stick to that. Fine, except that the only one I have comprehensive coverage of is the preserved example, and I think that's wrong.