Thanks Barry and Brian. I agree with Brian and his comments are as I thought. I have a couple of thr conversion sets but without the index plate or spring loaded quadrant selector arm. The drawings in technicalities didn’t make sense with what I had. The conversion wouldn’t have been such a problem with the slightly later hand change Scotts with the right hand exhausts and left hand brake pedals but one would still have the problem with preparing for and positioning the index plate.