I've detail stripped my AF fullsize 9mm twice to clean including firing pin and extractor, one semi detail for the LEM. Haven't changed any of the pins. Has been about 2k since the last strip and none of them have shifted. Though the next time I'm going to measure and replace them just to be safe.
Your mileage may vary, though I like to keep a clean house. If you're even somewhat mechanically inclined, have some small tweezers a small precision screwdriver it really isn't all that hard. Just be mindful of springs/detents under compression, don't damage the flat spring, and be patient putting it back together since getting everything lined up on the sear axle and positioning the trigger return spring can be tricky *especially* your first time.