This is probably a stupid question but would a new one (rather than one the age of the frame) be ok and work with the down tube shifters?
It will work, road front dérailleurs are ore or less universally interchangeable and down tube levers aren't indexed for the front anyway.
@gbj_tester started
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It will work, road front dérailleurs are ore or less universally interchangeable and down tube levers aren't indexed for the front anyway.