1.  Flash RPiOS Lite image.
2.  Add ssh and wpa_supplicant.conf files to boot partition.
3.  Put SD card in DGTPi and plug in power.
4.  Wait a bit and then login via SSH using pi/raspberry.
5.  Change pi password to picochess.
6.  Run:
    sudo apt update
7.  Run:
    sudo apt full-upgrade
    Reboot. Login.
8.  Run:
    sudo raspi-config.
9.  Set Localisation options (Locale/Timezone).
    Set Locale. Reboot. Set Timezone/Hostname. Reboot.
(If there were perl errors when setting locale since you are using ssh. See https://www.linuxbabe.com/linux-server/fix-ssh-locale-environment-variable-error for more info.)
10. Set Locale again using raspi-config. Should be no errors now. Reboot.
11. For keyboard see https://pimylifeup.com/raspberry-pi-keyboard-layout/.
12. Adjust .bashrc to your liking and type 'source ~/.bashrc':
    alias ll='ls -lA --color=auto'
13. Run:
    sudo apt install git avahi-daemon avahi-discover libnss-mdns sox libffi-dev libssl-dev libfontconfig1-dev libsdl2-dev libsdl2-ttf-dev zip unzip qtbase5-dev qtchooser qt5-qmake qtbase5-dev-tools libopenblas-dev python3-pip
13a.Upgrade pip:
    sudo python -m pip install --upgrade pip
14. Shutdown. Move SD card to (Linux) PC.
15. Copy picochess folder from backup to /opt:
    Open terminal at /opt folder in mounted source image. Run:
    sudo rsync -avh --progress picochess <path where picochess folder resides on pc>
16. Copy to /etc/systemd/system:
    dgtpi.service      --------\ 
    dgtpistandby.service -------> disregard these three if standalone.
    dgtpistandby.target -------/
    picochess.service  --------> copy the Desktop version if not using Lite.
17. Mount in DGTPi.
18. cd /opt/picochess and run:
    sudo pip3 install --upgrade -r requirements.txt
19. Shutdown. Move SD card to PC.
20. Replace /usr/local/lib/python3.9/dist-packages/spur/ssh.py with https://github.com/tfromme/spur.py/blob/master/spur/ssh.py.
    Check permissions.
21. Edit /usr/local/lib/python3.9/dist-packages/chess/uci.py and change line 949 to:
        if movestogo is not None and int(movestogo) > 0:
21a.For standalone, edit picochess.ini and comment out dgtpi = true, or set false:
    #dgtpi = true
22. Mount in DGTPi. Run:
    sudo systemctl enable dgtpi ------> skip if standalone.
    sudo systemctl enable picochess
23. Add the following lines to /boot/config.txt in the first section (skip for standalone):
    # For PicoChess on the DGTPi (overridden by the [pi4] section below when using the RPi4b wired to the DGT3000)
    core_freq=250
    core_freq_min=250
24. sudo reboot
25. For Desktop RPiOS in DGTPi, force audio to Headphone Jack for root (otherwise it always wants HDMI):
    sudo nano /usr/share/alsa/alsa.conf
    Change defaults.ctl.card & defaults.pcm.card from 0 to 1
    https://www.alsa-project.org/wiki/Asoundrc has more info.
26. Edit /opt/picochess/dgt/menu.py for audio volume depending on setup (PCM, Headphone, or Master) near Line 1139 so you can adjust volume level using DGTPi or Web interface menu.