I'm waiting for the pictures to get to my email. From what I can see on my '57, the threads are probably 1/2" pipe. The heads from the '70's have 1/2" pipe threads and that is the time the factory moved the sender from the manifold to the drivers side head. I also have a late '70's factory aluminum Q-Jet manifold on a 383, it has the 1/2" port for the heater hose and a 3/8" port for temperature, probably a temperature switch for emissions. My best guess for the temperature sending unit for a gauge in 1959 would be 1/2" pipe thread.
Last edited by 78buckshot; 05/14/2024 11:10 AM.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
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