I didn't use bootcamp at all, I don't think it's necessary. I did a fresh install of Tiger and told the installer to create a 20GB partition for it. After it finished, I downloaded and installed refit, then used the package it came in to create a refit cd (the instructions are found here) Then I installed Ibex on the remaining hard disk space. Once that was done I just booted from the refit cd, used the partition tools to sync the partitions and both OS X and Ibex are happily coexisting on my machine!
Yes, install GRUB to (hd0) aka, where it would natually put it. That's what worked for me, at least.