Changing the instrument cluster on an S3

[MingBlueMagic]

I have just bought a new instrument cluster for my S3 as a couple of lines in the DIS display are missing. I have instructions on how to change the cluster but have heard that I need Audi to recode the new unit to my car (or something like that) otherwise I won't be able to start it. I saw posted on another forum that a guy with an A6 just swapped the clusters and had no problems.

Even if I need to get Audi to do something to the cluster and/or car, can I temporarily swap the units to check that the new cluster works properly? I don't want to end up in the sitation where, because I've swapped the clusters, I have a problem with my car due to it not recognizing either cluster.