All the Gitanes I have seen with internal cable routing (either Gitane USA or Robt. Broderick's catalog scans) show the cable entering and exiting the TT on the top, usually with a little bit of brazed-in tubing guide..and most models with that feature did not use Huret DOs nor have that semi-wrap style stay.
But maybe you can find other scans...the metallic purple also could sway one towards Gitane, since that was a stock color, but since it's been re-sprayed it's a false clue.