For Polish tankers, use British tanker figures. The Royal Tank Corps badge is removed from the beret and replaced with a silver Polish eagle. With the 4th Armoured Brigade in Italy, they also wore their scorpion patch on the left side of the eagle.
Rank ingisnia was worn on the epaulets and under the beret's eagle, don't use British rank insignia! (edit: rank insignia are usually in silver with silver edging on the epaulets):
http://en.wikipedia.org/wiki/Polish_Armed_Forces_rank_insignia
Good references would include for North West Europe:
The Black Devils' March--A Doomed Odyssey: The 1st Polish Armoured Division 1939-1945
and for Italy - Concord's:
CPC6524 Battle For Monte Cassino: The Fourth Attack
Mike T.
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