Dash119
Senior Airman
The A-36 had 6 .50 Cal machine guns, two of which were located in the cowling under the engine. These have no nose guns and appear to have four 20mm Cannon in the wings. I believe these were ordered by the British as Mustang Mk IA and were then held back by the USAAF after Pearl Harbor. The designation would be the rare P-51 or P-51-1. It was the later P-51A, which was the first fighter version ordered directly by the USAAF, that was re-engined with the Merlin to become the P-51B.These are actually A-36 dive bombers, the first incarnation of the P-51. They had Allision V1710 engines. With a few modifications and the insertion of a Merlin engine, you have the P-51A.