Bill,
I would think that your A&P could "train" you to become an authorized person. He would then enter something into your log book and the airframe log book which would state that you are "approved" to perform that task.
NOTE: I am NOT an A&P or an IA. Nor am I an FAA inspector. Discuss this with your IA / A&P. See what he/she says.
However, every time the doors are removed and reinstalled, you would have to place an entry into the airframe log book, signing the entry and including your pilot's license number.