# rm /etc/systemd/system/getty.target.wants/getty@tty1.service
# cp /lib/systemd/system/getty@.service /etc/systemd/system/getty@tty1.service
edit this file (the last line, must be ADDED):
[Service]
…
ExecStart=-/sbin/agetty –autologin root –noclear %I
…
[Install]
…
;Alias=getty@tty1.service
# ln -s /etc/systemd/system/getty@tty1.service /etc/systemd/system/getty.target.wants/getty@tty1.service