[Ron in Quincy]

I just installed a new Brassworks 10 fins to the inch Radiator in my 30 Coupe. Had the same problem trying to install my motometer. It's the thickness of the taper in the neck of the radiator. When I tried to install my original radiator cap it wouldn't fit also. I had a repo stainless cap and it fit fine ( not as long a neck as the original cap).

Ron