There's a bellypan on the bottom of the engine, correct, designed that way. People do take them off (due to being a PITA for service, or losing fasteners or accidents etc), but it affects airflow under the car not to have them on. Also can make the hood flutter & shake at high/triple digit speeds. If you want to replace it, you might want to stick with OEM, they come with the necessary fasteners from what I hear, not sold separately.
