We had our 2001 ML430 in for a service today and I asked the dealer to adjust the sunroof. When I got the car back, I was charged for the rubber bellows, and the service receipt said that the sunroof bellows were glued to the glass and could not be removed without damage. The sunroof switch was also cracked, but that's another story

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The WIS does not mention glue at all, and neither does anything I've read here or anywhere else. I am being charged almost $40 per side for new bellows.
Am I paying for an unexperienced tech, or were the bellows glued on earlier ML models?