Stripping out 1966 Plymouth Valiant Signet 200 2- Door

He may mean that the 200 and the Signet were separate models in '66. There were no "Signet 200"s.

Here's a scan of the brochure showing the 100, 200 and Signet: http://oldcarbrochures.org/index.php/NA/Plymouth/1966-Plymouth/1966-Plymouth-Valiant-Brochure