Any way to get more caster adjustment without newer adjustable CA?

You mean positive 3* caster? +3. Negative caster is for bias plys. Radials need positive caster for better tracking.

Yup. Positive. Spec is -2.0 to +3.0, more positive being better. Some people say up to 5 degrees is sometimes necessary. I can get mine to zero, but that's all the adjustment I can get. It tracks pretty well, and I don't know if I'll tear it apart again this year, but I think I want to get it a little better. It will track better in panic situations or handling situations that way as well.