Hmmm - US Olive Drab 41 (FS34087) comes up like that:


Not bad either...
Let's consider the facts we have:
F/O Geoffrey Bryson Fisken's NZ3072 was a
P-40M-5-CU, c/n 27193, Bu.No. 43-5505.
IRIS does not provide the M (Mk.III) model, but I think the Allison-powered E (Mk.Ia) version with the carburretor air scoop on top comes close to it.
This site
http://rnzaf.hobbyvista.com/p40col.htmltells about the colours of the P-40Ks and Ms:
"The first of the 'K' models appear to have been received in the Dark Green/Dark Earth/Pale Blue scheme with Red/White/Blue roundels in six positions and the wide unequal width fin flash. The demarkation between the upper and lower colours was in a 'wavy' form, not usually seen on any other P-40 marks.
As with the E models, these colours were probably the U.S. equivalents. (Drawing B)
Later deliveries of K's were in the Olive Drab/ Neutral Gray scheme, and many appeared to have the spinner painted O.D.
On Operational aircraft, the central red dot of the RAF type roundels was soon reduced to a tiny 1" dot at first (drawing C), then by May 1943, this began to be replaced with a central dot of RNZAF Roundel Blue in various diameters. (drawing E)
This measure was adopted to avoid any large areas of red showing on aircraft, as this could, and was, often taken as being the Japanese Hinomaru during the heat of combat.
Most of these aircraft appear to have been repainted, firstly with the Dark Earth areas repainted in (NZ) Sea Blue Grey, then the whole aircraft was repainted in the Foliage Green/(NZ) Sky Grey scheme. Later aircraft were received in the standard USAAF colours of Olive Drab uppers, (some with the Medium Green patches on leading edge of wings, tailplanes and fin), with Neutral Grey undersides. (drawing D).
By May /June, 6" identity stripes in white were painted fore and aft of the cockpit, diagonally across the fin and rudder, diagonally across the tailplanes, and diagonally across the wings (upper and lower). These stripes were added to stop confusion between the P-40's and the superficially similar layout of the Japanese Ki.61 'Tony'. Needless to say, this measure didn't always work!
The surviving K's and M's were ferried back to New Zealand when sufficient supplies of the N's reached the Islands, and most were repainted in Foliage Green/ (NZ) Sky Grey. "Aircam Aviation Series No. 6 on the Kittyhawk Mk.I-IV in Commenwealth service provides some fine contemporary pics of ID-band-bearing Mk.IIIs and IVs and claims "Olive Drab" for the upper surfaces. Not a sign of "Foliage Green".
Still confusing...
Any more ideas?