CANBUS interface

Hello,
I would like to use this repository with our Igus Rebel.
I tried the CRI protocol via ethernet but encountered various issues and couldn't make it work.
I plan to switch to a CANBUS connection, but I can't find any documentation about the physical wiring from the robot.
Can you provide some schematics or a guide on how to connect to the Igus Rebel via CANBUS?

Thanks