Starting in May of 1930, all Ford Model A's that were assembled in France, came standard with Marchal headlights. Those Marchal headlights included completely clear, flat glass lenses. That was so that Ford Model A's would be in compliance with the new standard road code for lighting, which forbad any fluting in the headlight lenses, because fluted headlights supposedly blinded oncoming cars.
All road vehicles in France had until the end of December 1930 to come into compliance to that new road code for vehicle lighting, after which time fluted headlights would be forbidden.
Hope that answers your question about the headlight fluting.....at least for Ford Model A's that were assembled in France.
Brad in Maryland