1967 cutlass core supports... the mounting holes are always rotted beyond recognition. Ive never seen a NOS one to measure. From the ONE real nice edge on mine, im guessing 1 and one quarter inch diameter? If im gonna fix this thing, might as well do it right. Get out the calipers, and whose got a real minty one to measure for me. Thanks in advance, mike

 

I put the calipers to my rust-free core support in several different places and came up with an average measurement of 1.325" (+/- a few thousands). I'm guessing that it's supposed to be 1-5/16", to allow use of a 1-1/4" bushing.