For 5050LED strip.
The cover should clip in, but sanding and gluing in place may be better.
There's drill holes for mounting, The tabs could be cut off if not needed, or sink the print with the tabs pointing downwards (-8mm) into the bed.
Layer height makes a difference with how the cover clips in. So try to go for higher resolution. But infill can be lower 10-20%.
*Got some alternative covers to add soon,