Not sure about the area around the guns without seeing the photo in question.
However, going back to the original question - the 'Invasion stripes' and their appearance, would depend on the time period. By around September '44, most allied (fighter) aircraft only retained the under-fuselage stripes, as shown in the profile of Drew's A/c in the Osprey book (I can post this if required).
Of course, individual 'Personal' markings would also change with this progression - it depends on specific dates - as close as is actually recorded - as to what markings where when, where etc. Even that is open to debate, due to many factors.
In the 'Bottisham Four' pic previously mentioned, for example, Drew is actually 'guest' flying the nearest aircraft in the pic.
Bottom line - markings depend on a specific time (in days, more than likely, weeks at the most) in a fast-moving, though relatively short, time period .