Any luck on this yet? I believe I asked if you had a check engine light on. Does it show a code for anything else other than missfire?
Other thoughts I have, Perhaps a cam position sensor/crank position sensor. My car has two crank position sensors, one controls RPMS on dash, other controls timing. Might start looking at those sensors.
Please don't take insult to this, but how do you know you have a misfire? based on what the computer says? Can you feel it while you are driving?