I am having a problem updating Garmin G3X system. The GDU370 was updated from version 8.3 to 12.6 skipping several versions. The LRU's did not update. It was suggested to go back to an earlier version, one closer to 8.3. Does anyone have an earlier version they can share? Any ideas or suggestions would be appreciated.

LRU's Version
GDU 370 12.6
GSU 25 2.0
GMU 22 2.05
GEA 24 2.03
GAD 29 2.00
GTX 23 ???

The GSU 25 has a CAN bus error flickering between (0-10%).

Thank you.