Take a read of this...I compiled a lot of information that should answer most of your Q's.
http://w124-zone.com/?p=168

I did not upgrade my brake booster and the pedal feels perfectly fine. Don't worry about it

Let me know if you have any other Q's!

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k