The style of invasion stripes on the fuselage is definitely unique.
Actually it's a photo recce F6 Mustang. Not that unique in the stripes. They just didn't go as far down when the order came to remove the stripes from the upper part of the plane
Well, I cited P-51C because I have read sources that say modified B and C Mustangs were both called F6Cs. So this was built as a P-51C and fitted with cameras later best I can see.
It was most likely fitted with cameras when it rolled out off the production line. The 91 F-6C-Ns produced were created from the -10 block of P-51Bs (F6C-NA) and the -10 block of P-51Cs (F-6C-NT).