how to know if a duster had the sharktooth grille from factory???

The rally dash was only used in 70 and 71 duster 340 models. The shark tooth grill was used only on 71 and 72 Duster 340's and duster twisters. NO OTHER DUSTER MODELS NO MATTER WHAT PEOPLE SAY! :) Just like the factory 340 six pack or 383 Dusters. LMAO. No such thing.