Mathman, are telling us to give it up, as in to quite doing this?

Or, are you asking how we did this.

I blended the neck of L3 and A3 Xin Xin with magnets, then exported the A3 neck and up with the L3 neck down. Hacked the L3 .Cr2 to point to the new .object. The Bel/Hiro I did 2 ways if I remember right. One I exported all the figure groups of Hiro and loaded them back in to BelBel as morph targets. The other I created a new neck for the BelBel/Hiro neck by splicing the two in Wings3d.

There is also Shapeshifter at PhilC's site. It is a FREE Python script that changes head/bodies of all unimesh figures or any figures that use the same mesh.  There is a bit of neck distortion but I found that using a magnet with a large Mag zone on the head can fix it quite well.