On my 300SD you pry out the center MB logo and then IIRC you can pry off the horn pad. In the very least, prying out the MB logo will give you access to the bolt holding the wheel on (although mine was torqued and loc-tited so far that I couldn't get it even with a huge flex bar). Its kind of tricky, the pad overhangs the logo quite a bit and isn't all that flexible.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth