Thanks. I followed PhilC's idea (read it yesterday) and opened the full S3 obj and the headmorph obj in my 3D app. Indeed: he morph is for V3, and is located higher. When bringing it down to the exact height, and deleting S3's head to place it exactly point on point, I noticed that several points of the head and the body aren't exactly matched in pairs. This must at least cause a problem when texturing. I will now move all the headmorph points untill they are exactly on the S3 neck points, and then it should work: using a V3 headmorph on the S3 body. Must say I like this kind of thing more than posing. Thanks, I learned a lot.

I have tried prudent planning long enough. From now I'll be mad. (Rumi)