Its a pretty easy job - IIRC you just need a 17mm and 19mm open end wrench to get the filter off. The nuts will likely require some force to loosen. Make sure the fuel pressure has had some time to bleed off - so do it after letting the car sit overnight. Use some hose clamps on the soft lines to minimize fuel loss. There will probably be about 1/4 cup fuel in the filter so be prepared with some rags and catch basin. Also make sure the replacement is oriented correctly when replacing. Probably a 30 min job. Write the date and mileage on the filter when you put it in, as a favor to yourself (or the next owner).
Should also check on the hose clamps on the fuel pump while youre under there, they tend to loosen or rust off.
Every bosch fuel pump Ive had in VWs has whined, not a concern as long as its not howling and fuel pressure is OK. I put an inline resistor in my vanagon to slow down the pump which quieted it down, but wouldnt really advise that with the 968.
