Good to hear. What was it exactly?
What did confuse me a bit, that you mounted them to mnt/(directoryname) and mounted then, in example, from your other drive the /var to mnt/var.
Usually, when you mount your sdb1 to /mnt, it shows the subfolders from your mounted drive automatically at the tree under mnt.
I have learned also lately, that you should not mount a drive into a folder, what contains other files or directories, because that can mess up both filesystems.
Sure, so far you mount it into a subfolder it should work, but i was not sure, if chroot then find its way to the other folders what it needs.