The only hard part is knowing what you DO have to take off and what you DON'T have to take off.
You don't have to take off the entire top section if you know how to get to all of the bolts and you have the special ball allen wrenches.
I don't know on this, the one thing about being at the shop is you have most of the little parts that break when getting in there...Like the plastic.
Be sure if you DIY, split the intake and replace the rubber rings and the throttle switch. If you don't, you'll be sorry.
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS