Dear the Warden:

You only need to remove the three bolts holding the thermostat housing, then pull out the old thermostat and the rubber seal. Stick the new rubber seal around the new thermostat and put it in the thermostat housing. Be sure that the "spring" portion of the new thermostat points toward the engine, and that the arrow imprinted on the new thermostat points up vertically.

That's all!

Best regards,

Eric