Help needed!!!

Hi, Ive been trying to make an alien queen model using oinkerwinkles tools. I opened up the Hydralisk model and deleted the face and the body so I got that big head part (dont really know what it is). Im trying to attach that to the back of the head of the alien model from wc3sear. The problem is I dont know how I would do this, can anyone help?

Do you know how to use Geosetmerger from the tools ??? If not there's about 10 tute's around. The one on oinkers homepage is good enough. It's a great simple program, but not easy to use with big stuff like that o_O . You'd be better finding a modelling program like 3ds, gmax or wings (free).