Hi all, just wondering if anybody knows what the deal is with the various driveshafts used by VAG - some appear to be interchangable and some don't.

I want to replace the N/S driveshaft on my Avant - it has AJM engine and DUK gearbox (actually it is the inner joint rollers that have fractured and I thought it would be quicker to replace whole axle than fiddle with inner CV joints). I thought I could use something like part 8D0407451CX, however when I check through http://www.vagcat.com/epc/cat/au/A4/2000/223/52/2775785/ it lists 8D0407451NX and 8D0407271EK - two different ones... anybody know what I can fit? Or where I can find out? (sorry, still a newb to VAG cars). Thanks