@ld986 seems like it is screwed in with a gazillion screws. So, how difficult? Let' say it's a PITA and tedious but not to complicated. Check something like [https://www.youtube.com/watch?v=4OnVlU8ySaE|this video] If suck somewhere during this task, just post a couple of images and hopefully we can help you out further
[guide|21499]
While you work on your laptop, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has a device with the same issues as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.
Repair is War on Entropy!