An assembly for opening and closing a cargo opening of a motor vehicle includes first and second posts located at opposite lateral sides of the cargo opening, the second post being spaced laterally from the first post, an endgate able to open and close the cargo opening, and first, second and third brackets, each bracket secured to one of the posts and the endgate, and defining a lateral axis and an upright axis. The first bracket is secured to the first post. The second bracket is secured to the second post such that the lateral axis of the second bracket is aligned with the lateral axis of the first bracket. The third bracket is secured to the first post at an elevation higher than an elevation of the first bracket such that the upright axis of the third bracket is aligned with the upright axis of the first bracket.