First time is not painless, practice in a VM first can help, subsequent times it takes only minutes.
Create partitions for new location.
From live environment …
– Use partclone to backup your root file system.
– Use partclone to restore your root file system to new root partition.
– Use uuidgen and tune2fs to change the restored file system UUID.
– Chroot into new root file system and change any old UUID references in /etc/default/grub, /etc/fstab, /etc/crypttab, etc.
– For EFI systems mount efi partition in chroot and re-install grub.
– Regenerate initramfs’ using mkinitcpio -P
– Use efibootmgr to ensure new boot order is correct.
Reboot into your system in a new location.
I’ve cloned my system many times using this technique. Seems complicated but it really is not.
I always keep post update (usually weekly) partclone images of all my systems on backup media. I can use these for disaster recovery, ie disk failure, or to restore if the main system becomes borked. With recovery omit the UUID editing stuff.
If you have a fully encrypted system simply open the luks container with cryptsetup before running partclone. On your new location luks encrypt your root partition first. Include the new luks container UUID in the UUID editing steps above.