Depending on the year of manufacture, the mounting locations may vary.
Front bumper
-open the hood.
-under the hood we take out two pistons, release them from the clamps and remove the radiator grille.
-under the grille and from the bottom we take out the caps that secure the front bumper to the metal amplifier.
-unscrew the screw behind the license plate (or below the license plate).
-in the wheel arches, unscrew the screws that secure the sides to the brackets.
-with an assistant, carefully pull the bumper forward from the guides in the wings (watch the wires and hoses).
-disconnect the connectors of the electrical equipment (if any).
-(if any) disconnect the headlight washer hoses.
Rear bumper
-open the trunk lid.
-unscrew the two (four) screws from the bottom that secure the lower part of the rear bumper.
-in the wheel arches, unscrew two bolts on each side that secure the brackets to the body (you can unscrew the brackets from the bumper).
-with an assistant, pull the bumper back from the guides in the wings (watch the wires).
-disconnect the electrical connectors.
How to remove front and rear bumper, Nissan Terrano R50 (1997-2003)