Where to put WinPE 3.0 boot image for DS 6.9?

I know it's not officially supported, but I know it's been done and it works. I'm a bit lost at my current configuration since I was not the original one who setup everything. I also don't want to mess up the current WinPE 2.1 setup we have.

I've already downloaded the 3.0 WinPE tools and put it onto the server. Where do these files go and when I create the boot image, how do I point to it (if PXE Configuration Tool doesn't recognize it by default)?

Need a solution as we don't plan to upgrade until 7.5 is released.