A partition separates a cabin space from a bed space on a vehicle having a first side body and a second side body. The partition includes a forward-opening receptacle fixable to the first side body and to the second side body to span between the first side body and the second side body and includes a rear panel. The partition includes a modular assembly securable as a unit to a forward side of the receptacle. The modular assembly includes a front panel and a window glass configured to be translatably supported by the modular assembly between the front panel and the rear panel.