The upper part is bolted to the body. You would need to remove the lower part first, it screws to the upper part. It's a pretty major job. There are a few common rattle areas on the ML dash, if you could better describe the location the noise seems to be coming from, and the model year of your truck, maybe I can speed up the process.
Also how often does the noise happen, and when does it happen.

Gilly

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