I just bought a Cherokee 180B. The POH is intact, but I am having a hard time figuring out exactly what data to use for the W&B. I am using Avilution software on my Droid Tablet and their W&B program. I have the airplane profile setup to what I think is accurate. When I put me at 240lbs, the instructor at 200 lbs, and full fuel at 300lbs I am outside of the envelope. I found an online calculator a flight school had for their PA-28 180 and it also has us outside the envelope with this loading. If I put 80 lbs of weight in the baggage compartment I'm good. Is my thinking and results right on this?