How'd it come out?
That reminds me, if anyone wants to benefit from my experiments, feel free to print out the second image I posted and use it as a template for the front of the face. It's not perfect, but as you put it together you'll see what needs tweaking.
...At least you would have to start completely from scratch in your scratch build.
In case anyone wants to use my image, here's a basic scale to help you get it sized up: The width of the mouth on the main face piece is 6.5 cm, and the height of the piece is approximately 8 cm.
Have fun.
-Nick
EDIT: I just finished roughing the helmet out, the ears are a little low among other things, so I figure I'll just cover the holes, resin the whole things, then fix the problems with some good ol' Bondo. Here it is in it's slightly edited format...