How to rely on SDF outputs in creating Response Variables for suspension optimization?

Hello, Altair Community!
I am working on rear suspension optimization right now and I have a problem with creating response variables in MotionView Optimization Wizard.
As an example, I would like to know how to write an expression for Side View Swing Arm Angle in the moment of Vertical Wheel Displacement = 0
So, the question is: How to make a response variable correctly, relying on outputs from KnC analysis?
As I understand,
1. I should pick the right type of response variable. I need the "At Reference Signal Value" type
2. I need to write a Response Expression. And that is the problem for me. Because I don't understand how to get the value of the Side View Swing Arm Angle from the KnC outputs. Which of these should I pick (see the pictures below)?
3. After that I need to write Reference Signal Expression. And that is a bit trickier because the output for Wheel Vertical Displacement is in the "combined" KnC output for Wheel Vertical Displacement itself and Wheel Vertical Force (see the picture below). Which of these will give me the Wheel Vertical Displacement?
I believe it is a very popular problem, so I think someone can help me to solve it
Looking forward to the conversation!
Best regards,
Anton