Modal Analysis Using Ansys Workbench

I am trying to do a modal analysis of a single degree of freedom system in ANSYS workbench.

Here, in this system, a cylindrical mass is suspended between two O-rings (1 on each end).

I want to capture the behaviour of this mass for various amounts of squeeze given to the O-ring.

A separate cylinder is bored in to hold the O-ring. thus, there are two separate cylinders to hold the 2 O-rings. The O-ring is made of viton material.

I have the experimental values of stiffness and material damping for this system or the O-ring itself.

Now, i want to input these stiffness and damping values in ansys for the O-ring and perform a modal anlaysis for this system.

First, i would like to do a non-linear static analysis in ansys for this system and capture the deformation for the o-ring material itself. Then, i would like to use this result to do a modal analysis in ansys.

Now, I would like to know whether this is a right approach towards the problem.

I would want to know the suitable material model to be chosen to model the geometric non-linearity (a hyperelastic or a viscoelastic model). also, on what basis do these material models depend on (say mooney rivlin, yeoh model, ogden model)

also, how can i input the damping ratio available through experiment into ansys workbench ?

It would be of great help If you can answer to my query....

Thank you