So on a vehicle with kingpins, would that mean the line goes from the center of the rear axle, through the centerline of the kingpins, then through the centerline of the tie rod end bolts? Or for rear steer, the centerline of the tie rod bolt, then the kingpin? Just making sure I'm understanding this correctly, thank you :-)
Yes, that's exactly right. use a plumb bob and some masking tape on a flat, level floor to check those intersection points. On the race cars with altered wheelbase, we would bend the steering arms (cold) to make the Ackerman angles correct.
Jerry