On a 92 OHV, there will be a 3 bolt housing on the top of the intake manifold. You will lose a bit of coolant, but it's a good idea to flush the radiator while your doing it. Get a gallon of coolant, and drain off the radiator first. It will make your life easier when you go to clean the thermostat housing gasket.
Make sure to install the thermostat in the correct direction. Make sure it "POINTS" to the radiator. You will need the rubber Thermostat Seal as well, if you didnt get that.
Once you have reinstalled the thermostat and bolted the housing down, and installed the upper radiator hose, fill the radiator, and start the engine with the cap off. Run it for 5 minutes top! That will get it warm enough to help purge the airpocket. Shut the truck off, and add more fluid. you'll have to play with it to get the level back to the top.
Once you've gotten as much coolant in it as wll go, cap it up, and run it, being very wary of the temp gauge. Once you've test driven it, let it cool off and check coolant level one more time. Check for leaks. And you're done.