A GUI (graphical user interface) method is preferred. For example, can the new remote login feature be used for the purpose if the remote person has a Ubuntu live CD and know how to boot it?
The built-in remote login feature in question has been described in Ubuntu 12.10 Login Screen Adds Remote Desktop Access. Remmina maybe?
Best way to remote login on a Ubuntu machine from ubuntu/windows and OSX
This is very simple to do, I do it all the time. First you need to boot into some kind of environment.
sudo apt-get install debootstrap && sudo apt-get install build-essential
debootstrap --arch i386 percise /mnt/new_disk http://archive.ubuntu.com/ubuntu
chroot /mnt/new_disk /bin/bash
With a little work you can make a script to do all this for you, and have a rapid deployment setup that is really quite handy. Here is a guide that should help get you going.
i don't think a remote installment of ubuntu from a live cd is available, as the new install wizard requires the GUI to navigate trough the setup.. before there was a preseed function, but it has been compleetly removed.
the best shot you may have, is to try to temp install sshd on the live version, and see if you have any chance there
If you boot from live CD and the sistem get's an ip, then he could activate Desktop Sharing and you will be able to continue the installation. All you have to do is install on your computer an VNC viewer and guide that person to configure access to the target computer on port 5900.
ask your friend to issue:
note: port 12345 should be open in the router
issue:
adjust sda with your cases
Depending on disk size and the speed of the connection it will take a while.
You can pipe to tar -xzpsf - to compress the flow