Thinking about it, I believe there were some changes to UD and it might not allow mounting a former array device like that, if it doesn't leave them assigned and try to mount them manually read-only with the array stopped, like so:
mkdir /x
mount -v -o ro /dev/sdX1 /x
Replace X with correct disk letter, if the disk mounts browse /x to check contents, if it doesn't post the output of the mount command.
In the end to unmount use:
umount /x