you should watch caeser on national geographic. he's "the dog whisperer" and knows his ****. but i agree its a dominance issue and you have to show you are in charge. shock collars usually have settings like 1-5 and usually will give an initial light shock or a soft sound, the dog learns quick.
i'm sure it will be harder to teach the dog but he will still learn. getting shocked isn't that fun. you could always seek a professional opinion or GOOGLE!