Not True
The 1979 Duster was actually very special ... it was actually a merging of 2 of the 70's Duster Models of the 70's
Those being the Feather Duster specail fuel economy option which capitalized on the other Dusters sporty flair (340 Duster, Twister etc.) Feather Duster was a fuel economy strippy model package with special light weight parts and cam only with slant six EPA rated at 36 MPG on steel wheels (kinda odd that while putting every thing else light they didn't put light weight mags on it)
and the other
Twister option of 1971 & 1972 (often Twister & 340 options are confused but they were 2 separate options, this is because they often were ordered together) Twister you custom ordered it how you wanted it it had a hood strobe stripe oprion, and optional hood scoops, and you could add almost any other option you wanted.
For 1979 Duster started a base package with a Chrome logo, dual tape stripe on upper body sides and a strobe tape strip between the tailights, and fullwheel cover hub caps, a slant six engine, a special plaid uphostery (only avlailable on 1979 Duster and its twin the 1979 Sunrise Aspen)
Duster was for those who wanted something different from the standard base Volare but couldn't afford or didn't want a Roadrunner or R/T
to get a Duster instead of Volare you paid $30 extra for one without quarter window louvers and for Duster with louvers you paid $60 extra (most opted for withlouvers vs without for the sporty appearance ... (most also added the Magnum 500's to delete the odd looking standard hubcaps they look out of place with louvers on this car)
Like Twister you could add anything you wanted to that by paying Mopar extra money to get it.
So Duster Pictured for discussion is a Fully Loaded car special ordered... To get 360 V8 was $499 extra, T-Tops $600 extra, Tuff Wheel was extra, if this is original paint the tail strobe stripe delete was extra..
Most Duster orders wanted something different on a Tight budget so Fully Loaded Dusters are rarer and little know with lots of misconception for 1979 & 1980 I call these Ghost Dusters because so little is known/remebered today about them
FYI I am the owner of F Body Mopars on Yahoo
Walt