This is a simple snap on face plate set to customize the look of the Anycubic Linear Plus and to help prevent dust from collecting inside where the circuit board sits. You'll need to print 2 of each and they are labeled front (on either side of LCD), "left" (on either side of power board), and "right" (on the side with nothing on it). I made these a tight fit so that they will not rattle with normal printer vibration so a bit of pressure and slight bending of the piece will be required to get it to snap firmly in place.
I printed these display side up so that they'd have a nicer finish. Doing it this way does require support but that side is completely hidden so it's not a problem.
Clean up support and snap in place. They are a tight fit so you may need to insert the bottom clip, then bow/bend the piece outward a bit on the edge to get the top to snap in. then just work it down until the whole thing snaps snugly in place.