Another thing to think about is the second to last picture up there. You can buy those mounts from northwoods or go get a spent 22 shell. They fit great for most feathers and you can make them very easily. Then you just weld it to the bell and mount it on your bird. I have heard that by doing it this way it will help prevent a deck feather from coming out. If the bell does catch a wire the whole bell and shell will pop right of. With the leather design you have more of a risk of a feather pulling.
"You're a smart kid Johny, you really are, but as long as I'm around you'll only be second best." The Godfather