Telecasters have been through many versions of wiring but around 1967 Fender settled on this arrangement which gave a master volume and master tone with a 3 way switch and is the version almost universally used now.
This layout is reversed so that the switch is furthest away then the tone and the volume is closest to the bridge.
There is no real need to shield the cavities in a Telecaster as the controls are mounted on a grounded metal plate. The bridge does not need a grounding wire as the ground is carried from the base plate of the bridge pickup and through the mounting screws to the bridge plate. The neck pickup has a grounded cover and so there is no benefit in shielding the underside of the pickguard as it does not cover any electronics. Just be sure to twist the wires from the neck pickup and to the jack socket.
Switch Positions:
1. Bridge.
2. Bridge and Neck in Parallel.
3. Neck.
Download Tele 3 Way Reverse Standard Wiring Diagram PDF
