Just chopping off the sick fuckers head is too good for him. Now if you really want to make an example of him do this,
Hang him from the torch. Right before he drops and the noose breaks his neck, cut off his dick and balls and shove them into his mouth. By doing this he knows before he dies that he is unclean and unacceptable to Allah. And then you leave him hanging out to rot and to be eaten by the crows.
But I'm sure you would have the ACLU and all the fucking bleeding heart liberals screaming bloody murder about his civil rights being violated. Screw them. Maybe they should go ask the families of the 5,000 missing people, many of whom whose bodies will never be recovered, because they are just gone.