Unfortunately it cannot be flashed to 4.x firmware. The highest it could go is 1.20.11 (Needs PCC 1.30.7 and PCTune 2.2.3 after the upgrade) . I show PCTune 2.0.2.3 as being the official version along with PCC 1.28.0.8. Unfortunately I do not have a copy of that version of PCTune. If another member does, i don't see that it would be an issue to have it posted.