No nuclear option?
I would emulate my Commanche cousins. It would take a while, but I wouldn't be wasting precious ammunition.
I vote for the "buried up to the neck next to a fire-ant nest" treatment... Or maybe the death of a million cuts... Or how about a group of concerned citizens and a good supply of rocks... Or staking him out in the Mojave covered in gravy so the coyotes can enjoy his liver... Or maybe... WTF? I'm an admittedly selfish b*stard. I'd just shoot him until the slide locked back, then pop in a fresh magazine and shoot him some more. I mean, what the hell......if it's worth doing, it's worth doing right!!!.