I have 2 colour prints of 01002 working on the breakwater which my late brother took in (I think) either 1978 or 1979. The colour of the loco is inconclusive due to the sun angle but it does look black.
My brother took me to the breakwater shed in July 1977 (he was stationed at RAF Valley at the time), everything was locked up but I was able to see the locos through a broken window and managed to get a picture of the side of the cab & number of 01001. It is definitely in black livery, though the funny thing is that looking at the slide through the loupe, the paint patch on the cab side where the new TOPS number was applied does appear to be a dark green shade to it, rather than black. I suspect that's probably just a trick of the light. Unfortunately I don't at present have any means of scanning the slide, if I can do so, I'll post it on here.
Douglas