Here is the file that changes Nightelf Male into Undead Male, it also includes all helmets working (all helmets that nightelf can wear, so if you wardrobe yourself with for example t2 mage helm it will still have a small bug since you shouldn't be able to wear that and i couldn't be arsed to change helmet you can't wear )
There is also a possibility you have a hole where your mouth should be, depending on what face your nelf has.
Anyway, here it is.
http://files.filefront.com/ScMtoNiMz.../fileinfo.html
have fun
/Langun