Answer:
From page 14 of the MiniSmart II Secure Smart Card Reader Command Interface (https://idtechproducts.atlassian.net/wiki/download/attachments/71697978/MiniSmart%20II%20Command%20Reference%2080161508-001.pdf?api=v2)
Get Internal Firmware Version Command Body is 78 31 – Get Internal Version Response Body is 06 + Version Number
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