Necklaces and Amulets can both be worn at the same time.
Gah, this post is about 40 minutes too late for me. I *just* disenchanted a regen necklace because I figured I couldn't wear it along with the Gauldur. And my enchanting is currently not high enough to re-make the necklace in the same strength. Oh well, good info for future. Thanks, BoS :icecream: .