If a dealer quotes you 3-4 hours labor, they should be taken out back and shot. I've done the job. I took my time since it was my first, and admittedly didn't finish in less time than that, but if I had to do it again, I could do it in under 2. I'd certainly expect your dealer tech to be able to do it quicker than I could.
But then, they don't call them "stealers" for nothing...

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2003 E53 3.0i
DOB 10/15/2002
Sienna red, Savannah Beige Dakota leather
Type FA53, Engine M54B30

2018 G02 30i
DOB 4/21/18
Black Sapphire Metallic / Canberra Beige Vermasca leather
Engine B46O