You mentioned that you do not want to DA yourself. If that is the case I would suggest that you not give anything in writing. When you are ready approach the PO. Tell him that "due to personal reasons I need to step aside (proper Theocratese)from my responisiblities as a MS. For the moment I would ask not to be assigned any parts in the Service Meeting and I plan on talking to brother School Overseer and withdraw from the school for now as well. I'm not sure for how long but this is something I have to do right now."
By using this approach you are not making anything formal. It is just like you cannot handle things right now and need a break. I have seen some bodies of elders use a simple note like you present as grounds for announcing you disassociated yourself. Never put anything in writing!
Many when they find out the truth about 'the truth' get an almost newfound zeal in preaching to others about what they learned. I am sure you have seen the zeal of a new person in the congregation and often they have to be told to tone it down or else they will turn off people with their message. The same 'righteous over much' attitudes are there with newly appointed elders.
Some when they leave the Borg can do the same. You know the people involved in your life. I don't. Just don't let your newfound information cause you to burn any bridges that don't have to be burned. Especially with your family. The softer the approach he better it has gone for many. Some (tipping hat to Farkel) have had better success with the 2x4 approach (tho Farkel really does have a soft side to him that helps too) but a softer approach will usually preserve familial relationships far more than if you are labelled apostate.
Regardless of how you do it, I wish you well and good luck. It is a tough time at first but the freedom and peace of mind that I found when I left the Borg is wonderful. The sense of liberation at being able to decide for yourself what and who you like without the Society breathing down your neck using guilt to control you.
My thoughts are with you.
Kismet