If its like the pop out door card type plugs you need a flat and stiff tool to pull the door panel right where they clamp into the metal. Harborfreight have a 5 dollar kit for this.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)