Speedometer does not work?

So, the truck listed above is my mother's truck (crew cab) and the speedometer hasn't worked in over a year after the transmission was rebuilt. After she had check around someone said it something somewhere might not be plugged and after finally looking for myself there is a broken connector on the transmission but unsure which connection or sensor it goes to if any has a diagram of that harness with the sensor would much appreciated or which sensor it could possibly be.