At the last scheduled service of my 2000 ML320 at about 50,000 miles, I was told by my MB service rep I needed to have the fuel filter changed at a cost of about $500. I decided not to have it done, but had no idea why a fuel filter would cost so much.
I found the information regarding the "product enhancement" after reading about it in this forum, and took the info, along with a copy of the TSB to my dealer when I had the truck in for new front and rear brakes and rotors at 57,000 miles.
They told me that they had never seen the TSB. They also said that since it was not a safety recall, the upgrade was not covered under warranty, but still needed to be done at the next service at about 60,000 miles, and paid for by me, since my vehicle (purchased new from them with the MB extended warranty) was out of factory warranty.
A couple of days later, they called me back and told me the service manager approved the update per MY COPY of the TSB under the "goodwill assistance" plan.
My dealer just performed the retrofit which included the new fuel lines and the new fuel filter. It was all covered under warranty.
Thank you all for the valuable information you provide in this forum.

jdrtina