Ok look at your strings at the back tires.... if the string is a bit off of the back tire at the front edge, then it is not a straight line parallel to the car's centerline. It is angled out a bit towards the front. To set tow, I use a bar with a fixed 'tab' about 12-15" long on one end and a moveable tab at the other end, both of which stock out of the bar at 90 degrees. Set it in back, then move to the front, to get a differential measurement of toe.
