Little slow on this one, just now saw it.
I don't doubt you one bit Haz. They can be hard to kill.
My dad had a go-round with an opossum that had gotten into the chicken pen one night. He had a 6" Colt Python loaded with 2 CCI snake shot, 2 .38spl and 2 .357 JHP. He keeps it that way for varmints and the like. When he got out there, the thing was cornered in the back of the coop. He shot it with both rounds of snake shot, (which did nothing to it) then both rounds of .38spl. By this time, my dad was wondering if he even hit the thing at all. The 5th shot of .357 JHP knocked him dead.
At the time, I lived on the same 'compound' as my parents. When I heard the first 2 shots, I jumped up and grabbed a .45acp. When I heard the 3rd and 4th shot, I decided to grab a 12ga as well and went running down the hill. Wasn't sure what the old man was shooting at by that time.
Turns out, after a closer look, all 5 rounds hit the little booger.
That story told, I have to brag a little bit. One night camping out at the ranch a opossum decided he wanted to join in on the Wolf brand chili being cooked up. While sitting in a chair near the fire, my buddy and I heard the leaves crunching near us. I yelled "LIGHT!" and pulled a 9mm from my holster. Before the light hit the bastard, I had put a round though it's mouth and throat. It only took me 1 round to kill that one.

Luck shot maybe, but I prefer to think of it as complete and total point shooting skill.