About an hour and a half - and a punctured thumb (goddamn hobby drill) later, I've got my first GK terminator magnetized. Weapons, helmets, and working on a magnet mounted on the backpack (for different iconography - SO MANY CHOICES) will be interchangeable.
This boxed set comes with 5 terminators and a whole lot of choices - the effort is worth it. As I refine my technique and it's a little more clean - preferably no blood next time - I'll be throwing up a tutorial on this. Time to get to work on the next termi.
Edit: Here's the second I've done. These models are amazing.