Surprising that nobody jumped on this, but then it has been discussed before. I think all of our resident techs here have said that it is not a DIY job. Leave it to a pro. Search the archives for more detail.
BTW, I had the dealer do it and the job was not terribly expensive.
82 300D Euro
12 Honda Pilot
14 Tesla Model S
Former MB: 86 190E 2.3, 87 300E, 80 240D
Chain Elongation References