About ten to 15 minutes and IMO it was very easy. Just remove the 4 screws (two on each side) and slide a flat blade around the edge to release the tabs. Then the cover just pops off.
Leaving the part I cut out off and just sticking it back together without the blue makes it brighter also, as a second option. Monokote makes 20 different colors, so I am going to grab a few different one's and try lime green, as well as tangerine and a few others. People with black books can do red and it would look amazing.