Write a letter. Write it on one side of one page. (Bethel policy). Don't make it long. Make it pretty damn biting.
When I put in my resignation letter, the elders still wanted to meet with me. In my case, they held off announcing it for several weeks because it came completely out of the blue. I had planned it all, and gave off very little as to my intentions. Reading here (lurking) during that time convinced me that I had to go out on my terms. So I planned it all out.
I moved out in a few hours to a new apartment, let my ex wife know that I was done with her in a seperate letter, and put my resignation letter with it. (we were staying at an elders house after coming back from Africa.)
I say, resign. I also say if at all possible, save the drama. Plan on leaving and leave. Who cares if it shocks them? It's a cult, a no win situation. You can't change them. You can only move forward.