Smiths reverse speedo trip odometer reset procedure

[767Jockey]

I found in my old parts pile a cable that I believe is the trip odometer reset cable for my Smiths trip odometer. I was always thinking that it's a push button at the end of the cable, but now that I look at it, it doesn't push but instead it rotates. Do I have the right cable here? Is that the procedure, to snap the cable into a hole in the back of the speedo somewhere then rotate the knob at the end of the cable to roll the trip odometer to zero? I looked here and online and didn't see anything on the Smiths mechanical speedo trip odometer reset procedure.