It is certainly not the right colour in the photos in Mini Magic. That's the colour Garry McGrath had it painted, and he based that on the colour Ron Williams painted the Broadspeed, but Ron painted the Broadspeed the lighter colour because he didn't like the original dark colour.
The colour Low'n'Blown has painted the Hopkirk/Foley Bathurst Cooper S is far more likely to be correct, but the Holland car may have been a bit darker still - appears that way in the photos from the day.
While the factory had its own interpretation of Castrol Green, most of the factory-supported cars were painted by the driver's usual painter and although Castrol Green was stipulated, varied considerably.
The photos on ausmini, as listed above, are the only colour shots from the day that I am aware of. BUT, be aware that the first listed photo (
http://autopics.com.au/don-holland-ligh%20...%20farm-1967/ ) is NOT the same car and is NOT Don Holland. It is Bob Holden in the factory-built lightweight. I have alerted autopics about this quite some time ago, but they still haven't changed it.
Watto.