The present disclosure relates to methods and apparatuses for assembling disposable pant diapers having contoured elastic belts. During the assembly process, opposing end regions of chassis are connected with the elastic belts in the form of first and second continuous elastic laminates. The chassis are then folded to place the elastic laminates into a facing relationship. The inner longitudinal edges of one or both the elastic laminates are then cut to define a contoured shape. Discrete pieces of trim material may be removed from one or both the elastic laminates, and the first and second continuous elastic laminates are cut in the cross direction to form discrete pant diapers. In some configurations, a single knife both removes the trim material and cuts the elastic laminates in cross direction. And in some configurations, a first knife removes the trim material and a second knife cuts the elastic laminates in cross direction.