My VP didn't have the steel plate. The ECU was directly behind the plastic kick panel.
Rip the kick panel off, your ECU should be staring you in the face (if not, it will be behind a steel plate as Stocky said), unplug everything from the ECU (don't worry, un-plugging everything won't do any damage at all to your engine etc), unscrew the ECU from the wall, then undo the 2 tiny bolts holding a steel cover that's slid over one end of the ECU, slide that off, then memcal will be staring you dead in the face. Just unplug it.