1/ The 'pass through' could go between two ribs, punch a hole in the heart and exit between two ribs.
The 'stay in' could hit the collar bone, deflect, and lodge against the back of the shoulder blade.
2/ The kill shot could enter below the ribcage, tear through the liver, aorta (the actual cause of death), and kidney and exit out the back.
The 'stay for a visit' round could enter just below the sternum (breast bone), nick the liver, pancreas, and a kidney and lodge against the spine.
One thing to take into account is the weapon used. If the gun's a .45, chances are it's going through him no matter where it hits. A weaker round like a .38 or smaller would have a better chance of not punching through the body.
Hope this helps.
Dave