Made progress with the diff. Have the Moser aluminum centre section in (lightened 3.50:1 gears) with a Wavetrac (http://www.wavetrac.net/) diff. Still waiting on the CV joints before the rear coilovers can be finished.
Man... I wish I woulda thought about having the back half of my SRIII frame like you did. I guess I'll just have to do another Vette when I'm done with the current one.
Great progress on your '64. That's gonna be a beast.