Well I tried that and I got this
Code:
mount /dev/sdb6 /mnt/dude_said_mount_here
mint mint # mount --bind /dev  /mnt/dude_said_mount_here/dev
mint mint # grub-install /dev/sda
error: unknown LVM metadata header.
grub-probe: error: cannot find a device for /boot (is /dev mounted?).
error: unknown LVM metadata header.
/usr/sbin/grub-probe: error: cannot find a device for /boot/grub (is /dev mounted?).
Now when I reboot I just a grub prompt which is a pain although thanks to your help not the end of the world.