The 2-way allows lockup or automatic(lets computer do it)
The 3-way allows lockup, forced unlock, and automatic.
When really putting the torque to the ground at low rpm's, the TC clutch will live longer if you unlock it.
The wire you use to ground on the 2-way for lockup, needs to be broke then run through a 3-way toggle switch.
Switch to ground=full lockup
Switch to make circuit=automatic
Switch to break circuit=unlock