I have had one of Tamiya's 1/48 scale Dinahs for a long time and recently have added the Eduard zoom set and some resin exhausts to the box to go with a Falcon vacuform canopy. I found a nice build-up on-line of an overall gray-green scheme with white panels under the hinomaru markings that I really like, and there seems to be evidence to back up this scheme.
The next question then becomes, what about the colors for the cockpits, engine cowling interiors, and wheel wells? I have seen the Dinah at Hendon myself, looked at a lot of pictures and models on-line, and have also studied Nick Milman's blog. I have also searched in what I think are the applicable forums here on BM.
I have seen light olive green, Japanese metal primer, dark blue gray, and something that looks close to RAF interior gray-green in one image or another of the cockpits.
Frankly, I tend to go with Nick's data, although in his blog I do not think the sample cited was a type III reconnaissance aircraft. Would any of you like to take a stab at this, including references, for the interior spaces on later-war KI-46 II recon aircraft? I am only going to do one of these and I'd like to get the details right.