Excellent advice. I have a set of ophthalmic surgical instruments and a head loupe for magnification. Still, I'm only successful about 80% of the time.The skin starts up the stem where the leaves are curled up. If you ran an exacto knife or pin up the stem you could catch under the membrane and pry it off.
Spraying with water and a drop or two of dish detergent will moisten it and make it easier. The dish soap helps the water penetrate better.
Sorry fellas but the seedling is looking exactly the same, it looks as though I'm going to be pulling her. Thanks for all of your insights though, at least now I know what to do in the future.
The casing doesn't seem to want to come off. I've posted a picture: