Hope not too silly question from a ISO builder newbie...

I have to build a minimal custom Kali ISO that only includes the packages that are needed for students to complete their computer security homework. I have prepared my new kali.list.chroot, updated the desktop image and links, and copied useful material to ease students' work.

Students will perform their exercises at the lab and they will need root privileges to complete their attacks. They are supposed to be hackers (not crackers), but they may execute wrong commands (the nightmare is rm -rf).

Therefore I want to disable automatic mounting of hard drives.

Is there a best way to do it?

Should I override some of the existing boot time scripts?
Or I have to add a new hook that unmounts disks? (this solution looks to me a bit too dirt)

Many thanks in advance.