'66 Biscayne- chassis adjustment for better traction-

[66cayne]

I have a '66 Biscayne, 496BBC, 4 speed, 12 bolt, M/T 10.5/29/15 slicks. I am trying to improve traction when I launch this thing. She is running 11.60s s with a 1.70 60 ft.. I have fiddled with slick air pressure, an airbag in the passenger side rear spring and different spring and shock combinations. I am now trying to adjust the instant center( where the 2 upper and 2 lower control arms would theoretically intersect if they ran through the entire car) more towards the center of the car instead of slightly in front of it (by my calculation, hard to do with the body on the frame). I understand this change in I/C will benefit planting of the rear tires and hopefully improve my launch/60 ft times. My plan is to change the angle of the two upper control arms so they will intersect with the projected line of the lower control arms more towards the center of the car. I believe by adjusting the angle downward on the two upper bars by about two inches it will get me there. I suppose this could also be done by lowering the rear mounting point of the lower control arms to achieve the same effect. Just want to hear from those with more chassis experience if I'm on the right track for attempting this change. Thanks