Installing headliner '71 dart swinger

The umbrella type headliner will be the most difficult R&R you'll ever do. Even with the front and rear glasses removed it's a chore. There are some tutorials on line that will help.
One thing I can add , cover the cars floor with old blankets or similar. The rear seat anchors can draw blood from your knees. I cover those with hub cabs and cover the hub caps with blankets.