No problem, I would like to be able to help through my own trials and tribulations if possible as I benefit from others' experiences. Maybe you have already run all the numbers but in case you haven't: (Please keep in mind that I am VERY NEW to all of this so I could be dead wrong in my logic and/or made some calculation errors). I ran through the all the numbers based on your post and your magic number with this set-up is around 19.35. I would agree that whatever challenge I face with the non GT version in getting to 21.0 or even close your challenge is much greater. Also, the GT is 19.6 out of the box so the mods seem to be going in the wrong direction. The non GT is about 20.3 out of the box though mine was about 4 g heavier than listed which helps a little. (Then again, at the same time we have to assume that the SW's we use are reasonably correct which could be a big assumption).