an apparatus for mounting a mold box on a machine for forming molded concrete products includes a mold defining a cavity for receiving cement having a pair of opposed side plates and a pair of opposed mounting brackets . a mold support frame is further included having a pair of opposed side beams and a pair of opposed end brackets , with a connecting device for mounting the support frame on the machine . a pair of opposed substantially parallel slots is formed on the support frame side beams and a sliding plate is receivable in the slots and slidable therealong . a slot is also formed on one of the mold mounting brackets , such that the sliding plate is receivable in the slot formed on the mold mounting bracket .