Rack Damper Adjustment Screw/Bolt - Old vs New

[bigfredb]

I have an 83 300SD. My engine is having some pretty large vibrations (bad enough to be tearing up my engine mounts pretty quickly) at idle. These vibrations change considerably as the engine warms up.

It was suggested to me to use the Rack Damper Adjustment to minize the vibrations. I guess there is also a New style screw/bolt vs the original.

My questions are:

1. Where is the Rack Damper Adjustment Screw/Bolt?

2. How can I tell the difference between the New style vs the Old?

3. What part do I order (if I need the new style)? (in other words, what is it really called?)

4. Is there a step by step DIY on how to make this adjustment?

5. What am I missing?