If it's ball joints, you might want to check on whether they are even available without having to buy the whole control arm. My old 400E didn't give me the option to replace only the ball joints. Check the EPC.

If you are going to do the front wheel bearings, I found that a cheap set of big sockets from Harbor Freight came in handy to drive the races back into the hub.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles