Not sure about the rear bumper but the front one has two bolts behind the number plate and two just below them on the air vent and two on the bottom just infront of the wheel's it just should slide out then.
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Rear..Open barn doors/tailgate...remove the plastic nuts down along the bottom of the opening...prise the bumper lip at wheel arch out while pulling the bumper back....you'll see the plastic locaters when you remove both bumpers ,making it easier to replace them..:thumbsup:

 

Thanks Guys this worked perfectly.

cheers