Are these the Vimeo examples you looked at?
Here’s the Rhino file used in the above
TutorialFiles.3dm (468.5 KB)
and here are a few more example files
UniversalJoint_example.gh (59.8 KB)
SliderArm.gh (16.9 KB)
SliderArm.3dm (315.1 KB)
Here’s another post where I shared an example of fixing a rigid body with a support
I hope these help. Let me know if any of it isn’t working or is unclear.