When I put a 2008 wide DIS cluster in my 2006, it took quite a while to clock it forward. Eventually, a friend of an ex work colleague wanted to borrow my VCDS and in return I borrowed some hand held thing that could change the mileage via the OBD port.
Like this..
https://www.youtube.com/watch?v=FGbHt6gvZm0
It took quite a few goes and required removing fuses, counting seconds, turning ign on and off and counting more seconds and putting fuse back and was quite complicated - it took me almost an hour of trying stuff and googling.
Still had one MOT with the very low mileage.
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