I don't know about gun camera with P-40 or P-38. But, if you have some others photos of his P-40 or P-38 "Florida Thrush" where we can see the entire aircraft, aircraft No and/or serial) I'm very interested...
Regarding my project, finally, my P-40F "white 104" will be a long tail with white tail with 5 victories during June 1943 (photo above). It seems that he flew a short tail P-40F "white 104" sn41-14104 only early in 1943 (January, February, maybe until April or May)