DeeBee,
My comment re Sqn code was in jest/tongue in cheek etc and of course the codes would have varied as the cab moved from unit to unit. I don't ever recall seeing an SH Whirlwind with black codes.
A monochrome photograph of XP405, taken in 1973 at Upwood and which now adorns my downstairs loo (I'm so posh, I have a loo upstairs and downstairs!!!!) shows the code in black, edged in white. A colour photo of XP338, hovering over the roadsign at Tern Hill, shows the letters 'W' and 'N' in black, a black serial number on the tail boom and a red/white and blue roundal which takes up almost all of the fillet behind the cabin and underneath the boom. Both 405 and 338 are Tern Hill aircraft and hence both were in the overall training colours of the period (1973 and 1964 respectively).
By the way, have I mentioned that a book called "The Borneo Boys" is to be published shortly and will probably be launched in December. It deals with Confrontation between Dec '62 and late '66 from the perspective of the Whirlwind and Belvedere squadrons, although RN and Army also get a mention. This book will, hopefully, correct the misconception in some other accounts, which tends to suggest that the whole show was very much Army beefed up by the RN!!
Old Duffer