If you are going to do a mount, that question/answer is obvious.
However, if you are going to tie with them, I personally would take ‘em off the skin (and not have to deal with all that goes into that process. Sort ‘em, gently clean ‘em, dry ‘em completely, toss ‘em in the freezer for a couple of weeks (kill the bugs). After that, place ‘em in ziplock bags (with a aromatic cedar block).
Nice friend and gift!!
Enjoy the tyin’…