Because I wanted to convert to this: https://www.thingiverse.com/thing:2665491 I couldn't use the old mount on the carriage side anymore. Therefore I designed a compatible new one, that slides over the backside of the extruder motor.
The chain with which it works is: https://www.thingiverse.com/thing:1735193
The author marked this model as their own original creation. Imported from Thingiverse.