Best guide I could find when I took mine apart, translated from Danish by good old google
The guide mentions the rear air vents, I'm not if the TDI has the ability for the rear air vents, and if it does I don't think its worth the hassle, it took me over 90 minutes and a lot of swearing/ cut hands to change the duct in mine when I went from a non-cd to cd version of the armrest for my MDI
clicky
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