Back on the day, I was able to coerce the Windows bootloader into chainloading GRUB, which then launched a netboot kernel and initrd for Ubuntu that contained the CLI installer. I don’t know if that’s still possible, but I only needed one hard drive for it and it worked great until the laptop sadly melted itself to death several years later (it had a desktop P4 in a 14-inch laptop chassis, so I was surprised it took that long to die).