Frank-
The reason I told you yesterday to do a search for the words "airbag replacement" is because one of the 2 messages you found specifically discusses the requirements for disconnecting the battery when replacing the airbag.
Most of the new aftermarket wheels from tuners such as Brabus for example require you to remove your airbag and reinstall it on the new wheel.
Regardless if you decide to keep your airbag, I would still recommend that you follow the same cautions outlined by Benzmac in his post on airbag replacement. Airbags can potentially be deadly!

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Bill Wood
MercedesShop.com, LLC