Be sure to observe the correct order of the crush washers etc when taking it part. You do want to use new washers to prevent leaks.
Also, take your time in positioning everything back to where the original location(s). Often people just get it in there and not position everything correctly.
Use a permanant marker and write the date and miles on the filter.
How many miles on the car? What kind of fuel cleaner did you use? When I first tried to get my daughter's "project 190" going, I used a bottle of Techron Fuel system cleaner and if anything, it got worse. I then read here how someone used a double-dose of Techron Injector Cleaner in less than a tank. Dubious I tried it by hard driving for several minutes. The engine now seems fine.
Keep us posted,
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)