[Racer-X-]

Is it a 4L60? Or 4L60E?

If you keep the factory fuel injection, keep the PCM and let that handle the transmission. If it's 4L60E, this is your best option. An aftermarket transmission only controller is required and expensive for that transmission with a carbed engine.

If you are going with a carb, and it's a 4L60/700R4, a vacuum switch and a 4th gear pressure switch are all you need to run the TCC clutch. Everything else is mechanical on that one. The pressure switch may already be present for the current PCM to use.

 

[Racer-X-]

The engine coolant temperature switch is more about using the torque converter churn (and resulting heat) to speed up the warming up of the engine through the cooler in the radiator. It's not that the TCC won't work as well if the fluid is cold.

Some "TCC controllers" have an input for a coolant temp switch. Most just ignore that particular input.