The top edge of the rear case is lightly adhered to the frame.

Pull the top of the rear case away from the frame to separate the adhesive and release the remaining clips.

If you're having trouble separating the adhesive, use an iOpener, hair dryer, or heat gun to soften it.

Remove the rear case.

During reassembly, perform the following:

If you're using a using a genuine Samsung replacement rear case, be sure to peel off any adhesive liners from the rear case before securing the top edge's clips.

If you're reusing your rear case, you can use some pre-cut adhesive to re-adhere the top edge if your existing adhesive is no longer sticky.

This is a good point to power on your laptop and test all functions before sealing it up. Be sure to power your laptop back down completely before you continue working.