The construction is similar to the newer Star Wars stuff, especially the Clone Troopers.
To get those guys apart, I start by taking a new razor blade and CAREFULLY going along the seams of the torso pieces. Try and work the blade in there to slice through the glue and whatnot. If you remove the head of the figure, you'll notice a seam running down either side. Get your razor and start splitting the neck in two, using the seam as your guide.
After about 10 or 15 minutes of working the seams with the razor, you'll notice the torso starting to split. When the split is big enough, get a flathead screwdriver (the smaller the better) and CAREFULLY pry the figure open, starting under the arms, then working around. If there's a little bit of damage, you can always fix it with contour putty.
When splitting the torso, be very careful when you get to the neck-- the thin plastic could tear.
If you take your time, it should work.
If not, there's always Hasbro's "Smack-It-Repeatedly-With-A-Mallet" Technique (patent pending).
