Use a good c-clamp, place a small socket behind the link pin, tighten clamp. This wont drive the pin through but you can take it to flush, then drive it through with punch as above. Have done it, does work.
Like 26incher said, sander or grinder. I use my hand held grinder to remove the swedge on the end of the pin then just pop it apart with my hands and a screw driver. Very simple. Wear your safety glasses!