Proflow has remade the now obsolete Cleveland Restrictor Bypass plate which is pressed into the block directly under the thermostat. CNC machined from brass and to the original dimensions It can be easily tapped back into the block to replace the damaged or missing original. Please keep in mind that Clevelands need a dedicated thermostat in order to partially close off the orifice when the thermostat opens, so as to direct the flow of water into the radiator rather than take the easier route and recirculate coolant within the block itself.