Here is an update and a new piece in the puzzle.
After having changed all the front suspension parts all shocks, bushes and the nylon spacer for the rack the car felt massively improved to drive. Far more stable and no nasty thumps in the steering wheel.

But there was still an issue with the rear end.
It felt unstable and just plain weird. I also started getting some uneven wear on right rear tire.

I purchased new rear bearings and Included the taper roller bearings. Decided to let my local mechanic do the job and it wasn't an easy task as it had rusted solid. The taper roller bearings were just completely dry and stuck. Rusted and impossible to move in any way. The garage spent half a day fixing it but it now feels 100%. Way more stable and just better to drive.

I actually think I'm quite pleased with the car at the moment

 

Guess what.. I was still not happy with the feeling of an unstable car. after the winter i put on the summer tires again and it felt horrible. tramlining and the steering was not going where i wanted it to go. so i finally decided to buy an overhauled steering rack from Germany. cost me an arm and a leg..

i really hope that will be the final solution.
will install it by the end of next week so i might be able to confirm this soon hopefully.

any words of advice from you guys that i can pass on to my mechanic?

 

new rack installed and initial reaction was just oh my god it feels so light to steer. like i never had servo before. Feels also very precise so i think all is good now. some tramlining though due to worn front tires so will get new ones.

 

new tires on. its steady and just perfect to drive now. this issue is solved!

 

I love reading resolved threads. Thanks for all the info!