I've pulled the subframe 3 times - twice for parts from a parts car and once to do bushings.
In all 3 cases, I simply got a big pry bar between the body and the subframe and bounced on it. Using this technique, I purposefully broke the aluminum core in the bushings to drop the subframe. Then, I carefully drilled two holes in what remained of the aluminum bushing core that was stuck in the body. It may not be the "right" way, but it's simple and fast and requires no heat or special tools.
Note: that's with the subframe bolts already removed, of course - just hammer those from below once the nut is removed and they'll come free