Things are going great, im nearly done on the arduino script.

Using CAN Hacker i was able to locate 3 key CAN message ID's of interest to me,

1. one with general gearbox state that is transmitted all the time 0x489
2. one that is used by the diagnostics tool to transmit, 0x6A9
3. and one that is used by likely the BSI to reply to requests by the diag tool, 0x689

I was then able to 'decode' how the readings where being sent back by looking at changes while triggering a change in the reading via a switch or gear shift.

And put this all into an arduino sketch to emulate the process of requesting diagnostics readings, 'translating' them into readable data, and displaying/logging them for review.