[odysseus]

I'm pretty sure there's a TSB to fix the perpetually off analog clock, but not to swap it for the newer cluster. My Cadillac dealer also refused the work, so I went to a Chevy dealer with my new cluster and had them send it out for reprogramming, so the mileage was certified to match. Although the receipt said that they installed it, a buddy of mine who works there let me do it myself at home. I keep the receipt in the glovebox, just in case there are any questions.

The big deal is if you don't get the mileage to match. The government considers that fraud and it will void your warranty since the dealer has no idea how many miles are actually on your car until the warranty runs out. I fix everything on my own cars, and have never had to take mine in for warranty work (knock on wood), so I don't worry about it, anyhow.