Hello, @Daringbaaz

You can check our existing tutorial for installing ionCube on Ubuntu 16.04, although the WordPress one-click install is using a newer version if Ubuntu the process is still the same.

You basically need to download the needed version of ionCube and then define in the php.ini file

You can check the whole tutorial via this link and ask if something is not clear:

https://www.digitalocean.com/community/tutorials/how-to-install-ioncube-on-ubuntu-16-04

Let me know how it goes.

Regards,
Alex