I haven't tried this but it seems to work. There is a program called Fpro.exe in the KPG-49D software folder used to upgrade the firmware.
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Originally Posted by KB1WIT
Funny story, Ver 2 will flash on a ver 1 radio. I got the firmware and did it to mine a month ago. Decodes and encodes like a champ!
BCD396XT, BC245XLT & Pro-164
Fleet of TK-8180, 880, 3173, & 3160