Is there a way in NX to simulate taking out and putting in below sheet metal covers ?
If you want to check the collision, use 'Move Component' command with Dynamic motion and Collision Detection options. If constraints are associated with the component, you need to suppress/remove them otherwise component will move with respect to the constraints.
Other way as Kapil mentioned, Use Extraction Path available in Assembly Sequence command. To know more about it refer to the video in the following link.
Testing: NX 11 | NX 12 | TCIN
TC 11.2 | TC Vis 11.3 | AWC 3.2