Hi there,
I design/specify rubber anti vibration mountings, so here are my suggestions:
1. mass
2. space envelope
3 Load spectrum,
This should include the direction of the excitation (x,y,z) and frequency if appropriate. This could include cylic inputs from the wheels (vertical), centrifugal ( lateral). Also ask for the magnitude and duration of any shock loads.
4. Required shock/vibration isolation attenuation.
5. Maximum allowable displacements in all planes
6. Required life
My recommendation would be to mount the unit softly in the Z (vertical plane),i.e at least 5mm static deflection. Use about 50% of the rated load capacity of the mounting, this should give reasonable durability. 'Double U' shear mountings are an option.
You will need to take care with the cables connected to the unit - these can be quite stiff, and suffer from fatigue/fretting.
I hope this helps
Tom Aspin