1972 Duster 340's had the 'shark tooth' grill also. The 1972 Dusters had the long tail lights where the 1970 and 1971's had the much shorter tail lights. Really only difference between them. The 1970 Duster didn't have the 'ridge' in the center of the trunk lid...I believe..I could be wrong on that. I do know that one of the early years didn't have that different deck lid (trunk). My 1972 Duster 340 does have the 'ridge' in the deck lid. Someone please correct me if I am wrong.
Terry