It's quite straight forward but it's in a tight space (need small hands).
To remove exisitng belt:
Have a look at this site for a detailed guide to changing the timing belt and other servicing matters. http://www.taligentx.com/passat/
This is the timing belt, I think. Takes a lot of expertise. Get the shop manual. If you screw it up, you can damage the engine.
how do you remove a 1999 vw passat radio
Yes
I have a 2004 Passat Diesel and it cost £160 for the replacemnt belt from a VW approved garage.
If it's on a 1.8 T I'll include an instructional video below in the "Related Links" section. Hope this helps you out.
vw recomend 100.000 but should be done at about 80.000
when should I change the cam belt on a 2002 VW Passat 1.8S with 48000 on the clock
To change the alternator in a 2008 VW Passat, first disconnect the negative battery terminal to prevent electrical shorts. Remove the serpentine belt by loosening the tensioner, then disconnect the electrical connectors and mounting bolts from the alternator. After taking out the old alternator, install the new one by reversing the removal steps, ensuring all connections are secure and the belt is properly tensioned before reconnecting the battery. Always refer to the vehicle's service manual for specific torque specifications and procedures.
$90 bones
http://phatcat_ed.tripod.com/V6.htm
timing chain