Ok guys, so I know that the XD diesels are not supported for tuning (which I would hope that it would eventually happen, because the available platforms are a PITA), but what about speedo calibrations? How does the Nissan system speedo work? Is is like the Dodge system where the calibration is done through the cluster in the scanner, or is it like GM and Ford where it is in the ECM? Has anybody tried to do a speedo cal on a diesel?