The wiggling needle means either a slightly kinked cable housing or a dry cable within the housing. The housing is easily kinked as its attached to the back of the speedo. Partially remove the cluster and slightly bend the housing so it goes straight to the back of the speedo.

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81 300CD (sold) 1972 280 SEL 4.5 (sold) 1966 250 S 4 spd (sold) 1974 450 SL (sold) 86 BMW 325ES (sold), 1973 280C (sold) 1988 300 SE.