Here are my baseline plans for my car, with 205/55/16 front and 255/50/16 rear tires, @ around 24psi front and 28 rear pressures to start.
ride height: 5" F&R.
Front:
Caster: 5 degrees positive
camber: 1 degree negative
toe: 1/8th toe in
Rear:
inclination of the rear upright: 7degrees
camber: 1 degree negative
toe: 1/16th toe in
I have not yet used these figures on a GT40,,,,,but believe this is a good starting point. A degree negative camber all around may be a bit much for some folks,,,but that is the roadracer in me, as is the pos caster.
Radial street tires, even DOT stickies like a little pos camber, but if you ever decide to run bias slicks or bias treaded tires, they work bettter with less.