Interesting reading in the link below.
https://warfarehistorynetwork.com/artic ... air-force/

P-400 “Hells Bells”, 347th FS/67th FG, Guadalcanal 1942. The planes were still in British colors of medium green and brown over a light blue-gray.
Bell’s P-39 was developed as a high performance interceptor whose performance was hamstrung by the deletion of its turbocharger. The lack of a turbocharger meant that the P-39 was limited to low level ops. The P-39 was best employed as a fighter/bomber and in support of ground troops.
The P-400 was originally built for the British with the nose mounted 37mm Oldsmobile cannon replaced by a 20mm Oerlikon cannon. Due to the United States’ entrance into WWII, the P-400s were redirected to the USAAC in the Pacific. There they saw much use in the island campaigns that typified the Pacific theater.