Alpina progressive rated spring set for e12 up to 6/81 and e24 up to 3/82 is listed as part # 31 33 620 . Listed as progressive but the fronts were linear and the rear was progressive if I remember correctly.
KSK's price in '96 was $810 : I can only imagine what the current price will be.
WTB E12 lowering springs
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