Before installing the front coil over, add just enough preload with the shock fully extended to keep the spring from coming loose. This can be done by tightening the spanner nut on the shock body until the spring is held in place.
With the upper StrongArm installed, the coilover can be attached to the lower control arm and mounted to the upper bracket through the spring bucket. Preload can be added later to set your ride height.
Once the coil over is installed and supporting the lower StrongArm, the spindle, disc brake assembly and outer tie rod end can all be re-attached to the truck.