I have run mismatched tires from front to back before. Always radials in the front and had no problems. I am leaning towards the tierods not being equal. If that is the case then I figure I should be able to measure each one from center to center, add the 2 lengths, then devide by 2 to find out what they should be and then set them both at that length. Then take the car to be aligned by a shop. Hopefully taking care of the problems I am having.

Jack