I was following the instructions by evildog on how to replace kingo superuser with supersu. Every step worked for me except the one in which they uninstalled superuser easily i can't do that because in my settings it is only showing me options to disable superuser and selecting this did not make supersu the authorising agent
It will not show you uninstall button. You've to uninstall it manually by using a root explorer e.g. es file explorer.
On ES

Tap on Internal Storage

Tap on " / "

Find /System folder an Tap

Find "apps" folder

Find KingoSuperUser and delete it.

Reboot
---------- Post added at 02:32 AM ---------- Previous post was at 02:30 AM ----------
It will not show you uninstall button. You've to uninstall it manually by using a root explorer e.g. es file explorer.
On ES

Tap on Internal Storage

Tap on " / "

Find /System folder an Tap

Find "apps" folder

Find KingoSuperUser and delete it.

Reboot