How to apply SpringConstraint to this chassis?

Help and Feedback Building Support
#1

I created this chassis for a truck, it’s working, but it has no shock absorbers:
image

I didn’t understand how to use SpringConstraint in this case, similar to what was mentioned in this tutorial.
How to apply SpringContraint in my case?

Please, open the original project:
truck-spring.rbxl (67.4 KB)