1989 Chevy Cavalier thermostat replacement

It is in a very bad spot at the back passenger side of the engine below/ beside the exhaust manifold. Probably have to get to it from underneath the car, and removing the metal coolant pipe that goes under the engine up to the back. There is 2 8mm? Or 10mm bolts that hold the metal pipe on and the thermostat is in there. Good luck!