Troubleshooting of vintage car steering wheel steering angle display device

I have a vintage steering wheel angle indicator.
This is at least 20 years old. This was broken and no longer working
We had to carefully disassemble and repair it while also understanding the principles.
This is a device that has a weight with an inclination angle of about 30 degrees and displays the rotation angle when it rotates.
It is very useful for new drivers and allows them to align the vehicle's tires correctly when parking.