Once they start clicking, its futile to rebuild them, the joint is already compromised.

These are the same kind you'll find at your local Advanced Auto or NAPA- I used them on my 300D and have had no problems in the last 4 months or so:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=220279179011&ih=012&sspagename=STRK%3AMEWA%3AIT&viewitem=

These are made in Germany according to MB original spec, according to my correspondence with the seller:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=120351526535&ih=002&sspagename=STRK%3AMEWA%3AIT&viewitem=

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