I personally would never mount sheds permanately. I like them detachable. I'd put the female end in the elk antler and the stud in your mount. That way if your ever decide you don't like the mount you can stuff a piece of foam in the square hole and you won't have that eyesore stud sticking out of it.
I've never mounted Elk Sheds but lots of Mule Deer sets and I use hose clamps and copper tubing. The copper is pliable enough to bend around the antler without messing up the burrs when tight enough to support as the skull plate and then use a felt fabric to cover up most of the mounting system. Just the band of the clamps shows. www.monstermuleys.info/dcforum/User_files/4b17ca2354c9cebd.jpg