Hah! Turns out the files posted in the original post were edited PMGs, not just a swap. Tested out the PMG for Male bow for the one above and the one in the pack files. The one above allowed wings and hands to be visible, whilst the ones I found myself in the Pack files ended up as the spirit's body only with no hands nor wings (the same went for the Male Sword Spirit file I've been looking for). xD Shame on me. 
It's not really "swapping", if they were edited >_>
I was under the impression that they were using the human frame, which they are not (Male sword has 37 bones, human/elf frame has 26), so they will indeed require rejigging for the human/giant frame.
It should be a pretty simple process, just merging some parts together.
If you look at my posts on PMG and FRM files in the development section, you can get a pretty good idea of what mesh attaches to what bone, and which bones both frames have.
Yes. I spend a good portion of my time looking at the human framework, and I still have no idea what parts it is actually comprised of. I recommend attaching wings to the Clavicles though, should be pretty effective, (I THINK..)
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