nicholas@mordor:~$ 
nicholas@mordor:~$ mount -o remount,uid=your-user-name-here /mnt/external 
mount: /mnt/external: must be superuser to use mount.
nicholas@mordor:~$ 
nicholas@mordor:~$ 
nicholas@mordor:~$ sudo mount -o remount,uid=your-user-name-here /mnt/external 
[sudo] password for nicholas: 
nicholas@mordor:~$ 
nicholas@mordor:~$ ls /mnt/
external
nicholas@mordor:~$ 
nicholas@mordor:~$ ls /mnt/external/
EFI  grub
nicholas@mordor:~$