The Removal & Installation of the headliner takes about 2 hours. We didn't remove the hood on this one as it was lite enough to do on the vehicle. The technician used a rod that props the hood up and a tie down to make sure it's down tight so he can push on the hail dents. We use specialized hail lights to see the dents more clearly than with conventional eyes.  Then we use steel tools to get behind the dent a push the hail dents back out.  When a dent is in a spot where it can't be reached then we use specialized glue and tabs to pull the dent bit by bit.