I'm not sure if you know this or not, but you can just download the boot.iso image, burn that to a CD, and let it do the FTP downloading that way. I'm highly doubtful that it will be able to in any way write to a differently-formatted hard drive. The boot.iso, though, will download everything you need just off of that disk; you won't need anything extra besides a connection to the Internet.

Let me know if I misread your question.