When I was stationed in New Mexico, I used to go hunt rattlers for fun every evening I had off. Whenever I would get anything over 4 feet long, I would skin it and soak it in antifreeze and after a couple days (don't really remember) I would take it out and tack it to construction board. Just be careful about the color board you use. I mounted, on a piece of 1x8 pine, a 6 footer for my Dad one christmas and it had blue spots all over it. Can you guess what color the construction board was? LOL I even stamped on the brass tag that it was a "Rare" Blue Diamondback, ?- 21 September 1991. I had to call my Mom to have her read the date for me just now. It is still hanging in my Mom's basement. And it still looks great.
Don't forget, that it is some of the best tasting meat deep fried. Everyone thought I was nuts for hunting them, but when it came time to eat, just about everyone was my friend.