I would stay away from Wd-40 on antlers, over time it will collect more dust than u want !there are products out there made for taxidermy that your taxidermist should be able to help you! I have a couple bottles I keep on stock to sell
Is it a quality antler mount or just a cheap plaque kit from walmart? I used to use the cheapos. Several years ago I learned to use taxidermist blocks to mount them and make my own plaques. The difference is night and day. Takes a little while to make a nice mount, but im slowly going back and remounting my old ones with the new method and quality plaques.