Monza V8 water pumps are a bit unique in terms of pilot shaft diameter which is 3/4" vs most smallblocks which are 5/8". You need to have the correct fan pilot size to match the hole in the fan you are using to maintain concentricity to avoid vibrations and bearing problems. All V8 Monza pumps are the "short" design but there can be subtle differences between various short pumps with the actual flange height. This will determine where the pulley mounts and will affect the pulley and belt alignment so it should be checked. Some Monza applications require a threaded pad on top for accessory munting, it will depend upon your application. If you need a correct pump and have a problem finding one I would be happy to try and help.
cjbiagi@yahoo.com