My limited experience with SBM does tell me that it use track 0, just like XOSL or even NT boot loader(if memory serve). No boot loader can be fitted into 512 byte(sector 0) completely other than DOS(which just load and jump to the active partition) or LILO(which jump to its on disk image, thus moving the file needs reinstallation) or GRUB(again jump to on disk stage2 which needs reinstallation when moved).

When I said steps on each other's feet, I mean this. SBM could step on NT boot loader for example or GRUB stage 1.5.

Just mention that so people know the consequence.