Fuel fill tube

Here are the differences. Dart body is 4 screws . Duster and demon 3. But the year is what the real difference is.

67-71 the flange goes on the inside of the quarter and the screws go through the quarter and thread into the flange of the tube

72 -76 the flange is on the outside of the quarter and the screw go through the flange and thread into the quarter. They also changed the difference on the depth of the recess of in the quarter on different years. That is why some caps stick out on cars people don't realize there is a difference. Get me a picture of your opening on the car. Steve 610-533-9917