GoPro kept on freezing up and not responding after a couple of seconds after startup. I tried everything software-wise and a few hacks hardware wise (sitting in the freezer for a couple of hours, trying out other batteries or sd cards, etc.). Finally heard that the image sensor would be the cause so I gave it a shot.
Really easy. I've started tinkering with a few devices and it it a ot of knowing what to unscrew (and keep track of where to putthe screws back) and clicking components in place like a Lego piece. Watch some iFixit or Youtube videos and you should be good to go!
Thanks iFixit, Youtubers such as JerryRigEverything, and lots of awesome people on the internet sharing advice and experiences.