70 a body heater box 73 duster

Green one is a 69 dart and the black is a 75 dart

Late 74 and up had the vent tube but it's the same bolt pattern and footprint as 73 and early 74

All 67 to 72 i have ever seen are the same except the early ones had a metal squirrel cage and most 71 and 72 had a plastic squirrel cage.