Need speedometer help

[woodiemike]

Not sure where to post this question so I'll start here. Hopefully someone can help me out. So here's the deal; I have a 31' Roadster that I have converted to a AV8. Trying to use the stock speedometer. I have a stock 40' rear end with torque tube. With cable hooked up it does not work. I took off the cable and put a drill motor on it and it works. I jacked up the rear end, put it in gear and you can see the cable shaft turning in the turtle. Put it back together and still nothing What am I missing???? Any help, guidance would be appreciated. Thank you in advance.

Mike