AC Thermostat

Upgrading my AC system with a Sanden #508 compressor. 1972 Plymouth Scamp, V8, Auto, original AC car. I am replacing the TXV and new hoses.
My question is with regards to an AC thermostat switch. I do not recall there ever being a switch in the original system but I am hearing that the upgraded system with the Sanden requires one. Any help?