Probably the majority of the Spits there were Mk.V's, but maybe some of the more knowledgable of the campaign can answer that better for you.
Spitfires were flown by the British, Australians, Canadians, New Zealanders and even the US in the North Africa campaign against the Nazi's... os there's lots of subject matter you can choose from for this GB! In fact Hasegawa makes a USAAF Spit in North Africa colors, as well as a RAF Spit with the sand filter intake, marked for N. Africa as well. You wouldn't have to go looking for decals that way.. (both are 1/48)
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what little research I did shows only the Mk.Vb, Vc and Mk.IX's in N. Africa