People, it works perfectly!!!
The 5-year old saga is over for me at least.
So, I bought a second hand instrument cluster (6105X5, 9657951680) from the Netherlands. The donor car had 74k kilometers. My car has ~82k miles, so no problem with getting more mileage.
I put it in, all the lights were on (same as if cruise option 2 with display is selected on the normal cluster). Programmed to use cruise control option 2 with display and everything stopped flashing. The odometer read ~132000, or exactly my mileage in miles converted to kilometers. The trip distance was also in kilometers.
Took it for a drive and everything was OK, everything works as it should be, up/down from the control stick and cruise display also shows when the stick is switched on. See attached photos. The only problem is that the odometer shows miles and the cruise control LCD also shows the speed in kilometers.
The cluster is from Europe, so bought a cheap Peugeot 206 black instrument cluster and swapped the plastic thing that shows the speedometer in miles and in small letters kilometers. This is a perfect match. See photo.
If I can somehow switch the cluster to display miles on the odometer it would be perfect, but I cannot do it in Lexia/DiagBox/PP2000, this is no such option.
Just to check that everything is correct, I swapped back the clusters with the original one and the mileage is correct. As far as I can say or understand this kilometers business is hard-coded in the configuration data of the cluster itself.
Let me know if you need more info.
Happy days!
New donor cluster. The black caps on the needles are off as I was scanning the plastic thing for the speedometer. Might someday print myself a new face.
Second photo of cluster
The same cluster, but with the face of Peugeot 206. So now I get miles in big letters and kilometers in small.