@Stiehler:
The chain of dependence is basically:
JB ->
KUAL ->
MRPI -> Python -> LinkSS
----
The JB instructions are FW-specific, so, find the right one for your FW version.
KUAL is basically just an archive to uncompress in the right place, as is MRPI.
Python & LinkSS are custom update packages, that you can install in one go via MRPI (see the MRPI thread).