[Larry]

Well to start with its very likely to be a 9th AF P-47D aircraft, taken on or after 4th June 1944, as that's the earliest the D-Day stripes were added, though as the white bands are chipped it's probably taken a bit later after that.

Its not a 405th FG aircraft, or rather its unlikely to be as its not taken at Christchurch of their base in France. However the scenery in the background does look like the Avon Valley in Hampshire, so it could be a unit based at Winkton or Bisterne.

Pat II might suggest there was a Pat 1 that was damaged or retired.

BTW - There was a 56th FG P-47D called 'Pat' 42-28543 coded UN - V and flown by Capt. Stevens but this was an 8th AF unit.

Lastly on your copy can you read the pilots name painted near the cockpit?