The issue is NOT the thumbscrews. The issue is the reproduction brackets are junk straight out of the box, --and have been for the 50 years that I can remember this being a problem. If you purchase the correct rubber inserts from Snyders, along with the correctly shaped outer clamps, and then modify the Vintique bracket to accept the correctly shaped rubber, these will work well and they will not fall off. Use the pads & clamps below on all years with the reproduction wind wing brackets.
Below are links to the two major pieces that you need;
https://www.snydersantiqueauto.com/P...earchByKeyword
https://www.snydersantiqueauto.com/P...earchByKeyword
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