The outside jewel cover should unscrew normally, the light builb you have to push in and turn about a quarter turn...its kinda a *****. make sure your fingers are grippy...maybe get the tips of your fingers a bit wet and then dry them quick with a paper towel, then try....this sounds a bit odd, but you will see what i am talking about once your try to push in and turn....there isnt much clearance for your fingers.
but the outside jewel should just unscrew...even if you bust it you arnt looking at a lot of cash to replace it.