those three screws just need to be pulled out. I think I was able to get enough leverage to pull up on them while loosening them to extract them from the box. if that doesn't work, you just need to make sure the plastic clip things are all edged out so that the top can be removed, then just pull. it literally just snaps back into place when you go to reinstall. removing the screws I remember was important to facilitate the process, but not necessary. those clips all along the side are necessary, though. you should also remove all the fuses and relays etc, because they're helping hold that top part in. once you get the top part out, there are three "blocks" under it, with 3 wire harnesses. these just snap outof place if you pull (they were held in by those 3 screws), and under one of them is a 10mm hex that will help you remove the bottom of the fuse block and get you access to that bracket holding everything. HTH
Forum favorites: When darkmanX beat me in a roll, the cover page red Redline is right-hand drive, the GMPONE crew and all the other members I met, the few twincharged RL's out there, and of course my original purchases from Ron9919 which gave me my first mod bug.