Yo, flashG - is this duster you're making supposed to be the same as a "1971 Plymouth Duster 340"? if so I've got some crits for you... but I'm not sure they apply, as the car I'm looking at is called a 340 - might make a difference... might not. lemme know.
well, I'll try and leave out the stuff that seems to be for 340's only... though it doesn't look like much has changed.
I'll use a - for stuff I'm fairly certain about, a * for the things I'm not sure about, and a ~!- for the stuff that might be mods in the pic I'm seeing.
-brake lights too narrow - the reverse lights are almost vertically aligned with license plate intrusion on back bumper.
-grille inset too much - Perhaps distance on your model about twice as much as needed.
-rear side turn signals might be too low - their bottom is aligned with the top of the rear bumper, if not .5 - .75 inches above it.
-chrome trim around wheel wells
-chrome around grille needs to be more prominant... also the chrome around the headlights needs to flow and curve into the chrome around the grille the model appears to have them as two separate elements
~!-No body color on b-pillar (the pillar above door)
~!-Body color mirrors
*ridge on hood not wide enough near windshield
*Bevel on trunk not prominant enough
Just check your references with my crits, I might be leading you astray with these