Here’s what we do:

For vehicles with non-adjustable rear suspension:

1. Angle readings are measured at all four wheels.
2. The steering wheel is centered
3. Front wheels are referenced to the rear thrust line and set to specification.

Result: all four wheels are parallel and the steering wheel is centered.

For vehicles with adjustable rear suspension:

1. Angle readings are measured at all four wheels.
2. Rear wheels are set to specification. (Rear thrust line corresponds to vehicle centerline.)
3. Steering wheel is centered
4. Front wheels are referenced to the rear thrust line and set to specification.

Result: all four wheels are positioned straight ahead and parallel, and the steering wheel is centered.