GRUB2 combined with GPT made this whole thing way better. You make a partition with a certain type (0xef02 in gdisk's shortened codes) and that's where the GRUB

GRUB2 combined with GPT made this whole thing way better. You make a partition with a certain type (0xef02 in gdisk's shortened codes) and that's where the GRUB stage2 code goes; the stage1 finds the partition and loads it. It certainly eases my mind of "well, let's hope nothing decides to overwrite this 'unused' part of disk".