Hi rod the RAF did have some P38 lightings for evaluation but went no further, different from the usaf versions. cant remember what mk they were but some of the differences were that the raf version had the same engines on each wing to keep inline with only having a few different types of engines in service, so the raf engines rotated in the same direction, the usaf engines rotated in different directions counteracting each other. The raf also ordered the engine without the super charger on it ( from what i can remember) leaving it under powered. not sure what armament they came with either it was a long time since i red it and cant remember what book / magazine it was in. this might give you a research project and add them to your collection paul