That's actually a brilliant idea. Unfortunately it didn't really work so well in practice. It still came out very weird-looking, it didn't balance out perfectly so I had to manually adjust it and I never could get the head to line up properly with the eyes, and I think mixing in the base head cancelled out the morph.

I tried doing the whole body, just to see if it would work, but it told me it had the wrong number of vertices, even though it never said that for the head, and I didn't change anything or resize.