Fitting used instrument cluster

Hi guys I had posted to see about repairing the MFD on the instrument cluster so needless to say I need to swap out the clocks now. I successfully fitted the ribbon buy the screen hasn't changed at all same pixels are dead so unless the lcd screen is kaput? Anyways I'm going to source a second hand set of clocks as I think a new lcd screen was around £75quid buy I can source a set of clocks cheaper buy I need to know do the clocks need to be uncoded from the donor car or what's involved? I'm aware the immobiliser is in the clocks and thr mileage will need corrected.  So can anyone tell me what's involved and if anyone knows any vag specialists in and around Belfast that can assist?