You can find the jailbreak in the
NiLuJe's hacks snapshots thread, you will also need
the updated dev certificates as the ones in MKK have recently expired.
You want to first install the K4 jailbreak, then MKK, then updated DevCerts and after that you can install KUAL and subsequently KUAL extensions like KOReader.
I have the Kindle 5 NoTouch Black (2012) which I've found is nicknamed K4 or K4B here and have spent the entirety of yesterday figuring stuff out, I've actually joined the forum to post a KUAL extension I made that blocks Amazon's servers (except for the time sync ones) so MKK won't get remotely deleted as soon as you connect to WiFi
