Does anyone know if I can remove and replace the front lower grill on my 2012 Prius without removing the entire front bumper?
If by front bumper you mean all the plastic that the grill is attached to then no, you can not remove the grill without removing the lower plastic on the front of the car. (The actual bumper hides behind this cover and does not have to be removed.) If you want to see what is involved... check out the instructions for installing the fog lights.