Got mine back today. Rattle is gone. Service notes say they did the PCM calibration. The Stock file I downloaded with my ngauge is the same size and has the same modified date as the original. Not sure what to make of that. Has anyone confirmed that calibration is actually different? I also sent it to MPT so they can confirm my tunes are safe to re-apply.
I would not trust an aftermarket device to verify the calibration. 12A650 is the base PCM part number; 14C204 is the engineering part number. You would really need IDS to determine the calibration change.