Each version of Kernel needs only 1 (yes, one) update. This was all written by the developer in the Kernel Topic.
https://msfn.org/board/topic/181612-wip-windows-vista-extended-kernel/
Example, the last Kernel only needs the SHA2 update, other versions need other updates, you can all find it there.
For Vista SP2, the below step is optional (as per the original developer notes).
"3. Update your Vista to 2017 EOL version (especially install sp1,sp2 and the platform update)"