If you choose radials in a appropriate size, which is 205/85/R16 to replace a 7.00 X 16, I doubt you'd need alter the stock settings. Radial tires are supposed to have about 10% less rolling resistance and less tendency to wander due to pavement irregularities than bias ply tires. That suggests that keeping to the middle of the caster spec range and the toe out range might give good results with radials, assuming the chassis and springs are in good shape. With the correct bias ply tires, I'd go toward the high end of the caster and toe in spec range for best tracking stability. I'd use the factory camber specs. Cars won't steer unless they are moving, so don't crank on the steering wheel when the car is standing still. Get it moving, even at a very slow creep, when parking, etc. I don't know if a 205/85R16 is available in a lightweight tire outside of the specialty vendors. LT tires are heavier and stiffer than I'd want on a passenger car. I bought an LT 215/85R16 tire to use as a spare. It would not fit the trunk spare tire nest on a '37 120 convertible coupe. I never needed to run it on the ground, but I'm pretty sure it would have rubbed on the front fenders when turning. Based on that, I'm pretty sure a 205/85R16 would fit.
Non-power steering cars can be a little hard to steer when making sharp turns moving at very low speeds, such as when parallel parking. Usually, the steering wheel will turn more easily when the car is moving backward, since backing up effectively reverses the caster angle. Taking advantage of that when conditions allow can make handling the car easier. For instance, if you have to back straight out of a garage or narrow drive into a narrow street, make the sharp left or right into the street, then move the wheel back to center as you are backing the last few feet. That avoids turning the wheel to the extreme left or right while moving forward.