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Thread here about stainless steel: http://www.ybw.com/forums/showthread.php?438877-Exhaust-Elbow-S-steel-gradeIts an easy task, really requires only common sense rather than a lot of skill. As corinthmistral says, getting the hose off is the most difficult part. It really does not need a manual - its not that difficult, but I'm sure a Volvo service engineer will want to charge oodles. Simply follow the advise above and you will not go wrong.
Joha, I had heard that stainless would give a longer life, any comment, or recommendation.