I can suggest another idea, a little easier, but can you should still be careful.
Copy the content of the '/boot' volume somewhere else, unmount /boot, and copy the data to the directory. The catch is that the root volume must be a basic one or the boot loader must be GRUB2 (legacy GRUB can't boot from logical volumes). You can try to convert it and then get the source machine as it was. No guarantee though.
HTH
Plamen