In one embodiment, a gate insert includes an injection gate body having front and rear opposite sides and an aperture extending through the injection gate body between an injection gate outlet on the front side and an opening on the rear side. The injection gate body is connectable to and disconnectable from a gate pad in a cavity plate from a front side of the gate pad and from a front side of the cavity plate. In another embodiment, a cavity flange includes a molding body defining at least a portion of a molding cavity shaped to mold a shell of a closure for a container. The molding body is connectable to and disconnectable from a gate insert in a cavity plate from a front side of the gate insert and from a front side of the cavity plate. Other apparatuses are disclosed.