Dutton pheaton Steering systems
Dutton Steering is pretty well from the Triumph or Ford parts bin S1/2 is Triumph derived and S3/4 from the Ford Escort.
Nothing particularly special about the standard equipment apart from the Spitfire rack being a little quicker as standard than the Escort.
The Spitfire rack is only available as one type as far as I am aware the Escort rack is availble as an imperial version and a Metric Version depending wjhether it was from a MK1 or MK2 Escort or the MK2 using a metric M12 track rod end thread instead of the earlier Escorts imperial tread.