666 was advertised as early as Feb 1913, and was announced in March.
It was the only model made with the largest American 6-cylinder engine.
It is no longer mentioned in advertisements after Oct 1913.
The 646 appears to have essentially replaced it as the 6-passenger car
in the line,
being announced at the end of August in
1913.
Note the very small inset cowl lights, vs. the sidelights in the
windshield support on other 1914 models.
Click on a picture to see the full-sized image.
1914 Six brochure
Honolulu Advertiser,
Feb 2, 1913
American Vice President D S Menasco
San Francisco Examiner,
Mar 2, 1913
NY Auto show
- Pale green with gold striping Horseless Age,
Jan 15, 1913