I searched through past postings but did not find any reference to what I just found on two Carb Spacers. The hole for the PCV Hose Nipple is 1/4" NPT on one, (bottom photo) and 3/8" on the other. Admittedly, the 1/4" has a 1963 Part Number, C3DE-9A589-F, and the 3/8" a 1966 Part Number, C6DE-9A589-A. Was there possibly a running change made during those three years, or were there actually Spacers that varied depending on the car?
My Engine Block has a December 1964 Date Stamping, the Dearborn Coupe an estimated Build Date of January 23, 1965 and the Carburetor Tag has a first week of February Date Code. My question is twofold: is a Spacer with either a 1964 or 1965 Date Code acceptable and what should the hole size be?
Thanks in advance.
Ray