Local shops and chains aren't gonna cut it.
That is an incorrect statement. Many mechanics in the alignment business us the exact same equipment that the "high end dealerships" use, in some cases, even better equipment. I've lost track of the number of times I've had a car on the rack after a dealership "aligned" the car and had to completely reset it.
Back on topic, you should set the toe at 1/8", with radials, you can set it a bit tighter at 1/16". Caster should be 1.5-2 degrees positive. To check, you'll need an magnetic angle finder. Simply place it on a flat spot on the axle or spindle, get the reading. If it leans to the back, that's positive caster, if it leans to the front, that's negative. Positive caster is more stable, and will aid in proper tracking. Negative is less stable, but much easier to steer. Not many vehicles use negative caster, the only one I can think of off the top of my head are mid '60 Thunderbirds.
Toe is relatively easy, scribe the tires with a chalk line so you have a good reference point, then measure the front side and back side, then compare them.
On your tires, the 9" wheel should be ok with that tire, but with the high load range you're running, you may consider bumping the tire pressure up. running 35, you're not getting enough sidewall support. Try running 40-45 psi, should help the problem.
