Mark, those old ones look like they're from the days when we used to run pure water in the summer, then dump in a gallon of Prestone anti-freeze to bring it down to around 0F freezing point and call it good, then flush the system in the Spring leaving crystal clear water in the system for seven or eight months. Of course that was before the "expansion tanks" to keep the radiators purged of air, too, so rusting internals was rampant.