I recently pulled the 4 blade fan assembly off my '67 326 engine and replaced it with a fan clutch and 5 blade fan (factory style.) My question is this-my neighbor (who's a Camaro guy, but I don't hold that against him) says that the fan should ideally be half shrouded and half exposed for optimum cooling effect-is this correct? I never took notice to how the other fan looked. At present, I would probably have to install a 1 to 1.5 inch spacer to achieve this positioning. Any suggestions? Thanks!