Hmm, sounds like there's no easy approach to this. Might just have to document the change and live with the 24,000 km decrease on CARJAM. It doesn't bother me and to be honest I'd live with it if I was going to keep the car forever, but I will eventually be selling it to buy a house in a couple years and worried it might hurt the resale value.
Is what it is, I guess it would be OK if I keep the broken cluster as proof. Would've been nice to keep the records clean though.