Modifying filesystemMount System partition:
mount_apfs /dev/disk0s1s3 /mnt1And modify fstab using nano:
cp -a /etc/fstab /mnt1/etc/fstab
nano /mnt1/etc/fstabChange disk0s1s1 to disk0s1s3 and disk0s1s2 to disk0s1s4. (or the new system and data partitions disks based on the device.) Press CTRL-O to save and CTRL-X to exit.
Now we have to add SEP to the second system:
cp -a /usr/standalone/firmware/sep* /mnt1/usr/standalone/firmware/
Also add the baseband firmware:
cp -av /usr/local /mnt1/usr/local
The baseband is located inside of /usr/local, and the firmware names vary across devices. We can just copy it since the /usr/local path does not exist on the new system.
Modifying data partition
Now we have to move /private/var to new Data partition:
mount_apfs /dev/disk0s1s4 /mnt2
mv -v /mnt1/private/var/* /mnt2