Where is the plug on the transmission to disconnect the TCC solenoid? I am trying to diagnose a lockup issue and need to disable the clutch from engaging for a test run.

 

You may want to try to depress the brake pedal just enough to turn on the brake lights, this should disengage the converter when you feel like you would like it off.

There really is no way to just unplug the tcc solenoid in a late model 4R75W without cutting a wire, but this will set a code.