I believe John has nailed it in that EBY-D part number does sound like a teapot 4 barrel intake for a 256 Merc.  This would have the smaller ports and be a suitable intake for a 239 without worrying about the gasket mismatch that occurs when using the later model intakes.  

Another intake not brought up very often is the ECB-B intake which is the teapot 4V intake for a ’55 Ford.  This particular intake also has the choke housing as part of the intake like the EBY-D intake but instead has larger ports.  The 1956 4V Teapot intake (ECZ-A) does away with the choke housing flange on the manifold and the choke coil is instead located at the carburetor instead of on the intake.

Lorena, Texas (South of Waco)

No kidding.. I Accidentally bought one of these thinking it was a ECZ-B Once.. saw the "B" in the ad and was still learning about Y's so didn't know any better.. It was cool though.. rovision on here needed it so he got it..

Dustin

Southern Oregon Y's Guy

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