That came out rather nicely, although I ended up not actually using the head swap except to get it scaled to SP3 size, and steal the morph targets out of the head and neck.  It seems like the head swapper leaves the geometry un-welded, so I took another route from what it seems other people usually do, but this works well for me.  V3 head morphs on SP3 body.  Had to manually position the eyeballs, and I did make use of the morph splitter script and smoothing as JoePublic suggested (thanks JoePublic).

SP3 is really a very nice figure once you get away from the standard head.
edit: hmm, got some big feet tho.

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