Location of the transmission speed sensor / sensors

I am trying to locate the exact location of the trans speed sensors, I have looked searched for any diagrams on line to show / display the correct trans, but to no avail. My truck now is to the point when operated it will not up shift from the first starting gear, of course the abs lights, check engine light, and brake lights are on. In closing I just want to make sure I am buying the right parts.

Respectfully.