Clutch fan is removable. It should be easy to turn when engine is cold and have some resistance when engine is hot if working properly. Probably a thread explaining the process here. Try searching--remove clutch fan or just clutch fan.

Aftermarket radios don't cause any problems. There are several threads of step by step installation There is one active right now. There are several different brands to consider, all android based I believe and all installs are fairly similar. If you have a system with DSP it is a little more complicated by many of us have been through it and can help if you get stumped. I suggest choosing a brand that has a US distributor.

If you don't have a service manual like the Bentley offering, doing all the things you are doing, I would purchase one.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas