Upgrade to 35 spline Axles, 5/8"wheel studs.

I have a good friend who ran a all steel 69 Chevelle @ 3500 lbs+
All Motor 572 BB, 900 hp, turbo 400, 9" with 35 Spline Axles, all Strange parts it ran high 8.90s-9.00s on a 10.5 tire.
Neat car it looked like a street car you could cruse around in, the cage
was tucked up nice and tight with a full interior.