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Having a chat with another SV6 owner last night, we were both of the opinion of wanting to upgrade the instrument cluster. No idea though how easy (expensive?) it is though.
The first road wirthiness inspection will fail you because of the HID lights. They are illegal unless factory or comply with factory. If your model didn't have them off the line then sorry sunshine, you loose.
+1 for hid's, however yes : every 3rd car seems to have them lately...
As for the clutch, unfortunately unless you have proof of them riding the clutch or flogging the car to wear it out, you havent a leg to stand on. also, there's a 90% chance it was almost worn when it went in to them, how many klms?
If the flywheel (dual mass) has wear, it often sets off a chain reaction which causes slip and clutch failure.
Otherwise if you're over the 100,000km mark, it's not uncommon for a modern clutch to be worn when driven more than "sedately".