If you pan on re-using the Upper Control Arm the Pickle For will destroy the Rubber Boot.
It is difficult to predict how one it will take someone to change what you are calling the Inner Upper Control Arm Bushings because once in a while the Bolt is rusted into the Sleeve inside of the Bushing and People have had to use a Sawsall to cut throught the Bolt and part of the Arm to get it apart. But, that is the worst case.
Best to read the Repair Links and see the issues that people have had doing the job.
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I have never changed the Upper Control Arm Bushings so I cannot comment on removing the Busings and replacing them.
I would plan for the worst and have another ride available and hope for the best.
Remember not to torque the Bolt and Nut that goes through the Body till after the car is sitting normally on the Ground.
The below is how Mercedes wants it done.