All, I just want to point out that the NAPA thermostat referenced by Mike is a standard-flow version, Cleveland-correct design. There is also a high-flow Cleveland-correct version and THAT is the one Robertshaw has discontinued. I have heard the OEM unit from Ford was of the high-flow version. I have not read any definitive analysis of actual performance differences between the standard and high flow designs. What Marlin does is machine the “hat” and add it to the high-flow Windsor-correct thermostat, thus duplicating the unobtanium high-flow Cleveland-correct design. Photo has high-flow on left, standard on right. Larry All, I just want to point out that the NAPA thermostat referenced by Mike is a standard-flow version, Cleveland-correct design. There is also a high-flow Cleveland-correct version and THAT is the one Robertshaw has discontinued. I have heard the OEM unit from Ford was of the high-flow version. I have not read any definitive analysis of actual performance differences between the standard and high flow designs. What Marlin does is machine the "hat" and add it to the high-flow Windsor-correct thermostat, thus duplicating the unobtanium high-flow Cleveland-correct design. Photo has high-flow on left, standard on right. Larry [cid:356B10F8-04BE-4AF1-9D99-A8662A2216C4@attlocal.net]