72 dart headliner

First you need to check your roof structure for the holes that hold the bows. There should be 5 sets of 3 holes per side. If you have the holes, you need to get a headliner bow set, a headliner, and some sail panels

As far as build date, do you have the fender tag or the vin sticker from the driver door? My build date is found on the second row up and to the left of the order number.