Duster Doors and Trunk Lid

Would a pair of 1974 Dodge Dart doors work?

Not without a lot of work. The outer door skins are the same, but all of the mechanisms inside are different and have different mounting points.

Not to mention he has a '71, so he probably doesn't want doors with the plastic upper trim pieces that the '73+ doors have.

Here's a thread that shows the differences between Duster doors and Dart doors.

http://www.forabodiesonly.com/mopar/showthread.php?t=331898&highlight=duster+door