Hi Jim,
I have:
Avia B.71 WNr.165 coded SE+DZ
Avia B.71 WNr.167 coded SE+EA
...I've not got anything for WNr.166 either and the fact that the Sktz codes above go in sequence points to their possibly not being a WNr.166 allocated to the Luftwaffe?
[source, the defunct "Beuteflugzeuge 1939-45 Website"]
There was also quite a comprehensive article on the B.71 with the Luftwaffe in the defunct Luftwaffe Verband magazine, so I will check this out when I get home later...
Out of interest, we also have a large thread on Luftwaffe B.71's over on the LEMB
here (membership of the LEMB is required to view the thread)
Kind regards,
Peter D Evans
LEMB Administrator