The door and lid will physically fit but the lid will be missing the ridge down the middle and the door will be the metal top type, where as the 73+ doors have the plastic covers at the top of the door panel. Not sure about the window mechanism.
yup if you bought the 73 doors they use plastic door tops the 70 doors use a metal top that was part of the door i know were there are some 70 dart doors if you are interested
You will also need to use the window trim and wetherstriping from the 73. I don't know what they did but the window will have a gap around it if you don't change that over.