Clint
While the photo gives retractable landing gear a whole new meaning, the serial number is hard to read, probably because being partly covered in dirt and quite possibly also after receipt of an added bonus of some sandblasting....
Just to play a little with the digits here, what do you think about DFW (Av) C.156/17 or perhaps an 8 instead of a 6?
Just another shaky theory of mine....
Cheers
Stig