Would a whole turn signal/wiper switch arm work?
I have them removed and ready to ship for any reasonable offer,
with or without a cruise stalk.
PM me if this would fix your issue; it was the source of my issue with wipers not working on intermediate setting....

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1990 300D 2.5Turbo, two tank WVO, daily driver 300,911
1992 E300 gaser, 150k. Parts only, For Sale

[B]1984 300TD Euro 4speed Sold
1977 300D Elsbett SVO single tank Sold
1981 300TD "Silver bullet" 285k ran B100 Sold
1981-5 300D x 5 cars stripped and reused, parts for sale

Other toys:
1995 Dodge 2500 Cummins 12V P7100 Bosch mechanical pump with 2 tank veggieconversion kit, only 120k!
1959 Cadillac Dad's legacy, needs finishing