Did you install sysvinit-core? After reboot the inittab file should be there, I forgot systemd init does not use the inittab (i should recommend to edit the inittab after reboot).

After installing sysvinit-core and rebooting, you should be able to edit the /etc/inittab file. Then you can invoke:

# telinit q

This will command sysvinit to reread the inittab and it should terminate the useless gettys.

I have edited the main guide to address this issue -- please let me know if it works!