I don't think there is a difference in the 2005 and 2006 cluster as long as they are from mk4 and not mk5 cars. I could be wrong as I haven't done research on this.
Off the top of my head, I know that you need a new wiper stalk for cars with MFD, and an instrument cluster from a Euro car as the tachometer will be off if you get one from a gas car. You will also need a VCDS from ross tech and another tool to get the SKC codes to work with the immobilizer system which is in the cluster.
Also, post moved to mk4 section and title edited since it's pretty technical question.
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