Depending on the year of manufacture, the mounting points may differ.
Front bumper
-open the hood.
-under the hood, we Unscrew the screws, release them from the retainers and remove the radiator grille.
-under the grille, pull out the pistons that attach the top part (inserted from top to bottom).
-turn the wheels out of the way.
-(if any) in the wheel arches, Unscrew the screws that attach the undercarriage (front part).
-Unscrew the screws (screwed from the bottom up) that attach the corners of the bumper to the brackets.
-Unscrew the screws on the bottom side that fasten the lower part.
-with an assistant, we pull the bumper forward.
-remove the connectors of electrical equipment (if any).
Rear bumper
Removing the rear bumper is easier with an amplifier.
-from the bottom side, we Unscrew the nuts and screws that attach the bumper booster to the body.
-the bumper is attached to the amplifier with screws, pistons and latches.
How to remove front and rear bumper Chevrolet Express (after 2003)