Not sure I am following what your suggesting. I have an MSD Pro Billet distributor and I probably lack the skills to determine if my rotor is 30 degrees advanced, not even sure how I would know this.
What you want to be sure of, is that at about 30 degrees advance, the rotor lines up with the spark plug tower. To do that you would need to have a hole in your distributor cap. being that I do not have that type of distributor, Perhaps someone who does can assist you.