Hats off to you for doing this, I was going down this road as HM AWD headers had become unobtanium. Mal did have his shop for such a build, but I ended up with AWD HMs as supplied by Mal. I would love you to enjoy more of the reward of going 6G75 in AWD, mine are from the 6G75, the Headers, coughing up for Dr Johns Cams, and a TME tune. Dyno sheet posted. If you don't cam the TME tune is still worth it, but considers cams having swapped motors. Where ever you stop with hard parts the TME tune is worth it....