Generate Curve from Motion Path of a Bone (to animate steering of a fork lift) The bone in between the front wheels is following a Bezier curve (black) and the whole mesh of the forklift (all in one object) follows. I need the motion paths of the wheels (more precice of the wheel bones) as a curve!

Reason:

I want to make the wheel bones follow that curve and point in the direction of movement (for correct steering) and further make them rotate along this curve with a driver.
I want to unparent the wheel bones from the root and move them independently on their paths but in sync with the rest of the moving mesh.

Stuff thats not working:


I already tried to make the rear wheels steer by IK constraints and a driver bone which reads information of the bezier curve in front of the forklift but that does not do the job for me, since the radii of the Bezier curves I want the bone between the front wheels to follow are to narrow/ cover a too large range of radii.
I just can not bing this script to run. Perhaps somebody can explain how I do this step by step?
Btracer addon - I could'nt figure out how to follow the path of a bone which is parentet to another bone which is following another path (wheel bone)
The Motion Trails Addon isn't maintained anymore - not working on 2.8


Please help, I'm crying. The data is there in front of my eyes but blender does not allow me to use it
My good Buddy ClockMender has an excellent tutorial on this. 
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