I have a 1962 235 in my 46 COE and I used that 1/8 pipe thread at the top center of the head and hooked it up to my original 46 oil pressure gauge. It reads right in the middle of the factory gauge 15. Then hooked my after market gauge to the block that reads 40. At least one of them is wrong.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
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