I've got a 5GB Windoze partition (from Boot Camp) on my iMac that I'd like to overwrite with Ubuntu. I can probably just format that partition and install directly to it, but I'm worried about possibly overwriting the bootloader. When I tried dual-booting a PC a while back, it overwrote the Windows bootloader with GRUB. Will the Mac bootloader remain no matter what? Is there a way to prevent this from happening?