Howard used it too but that may have been after McGurk. The log on this one looks like the one in question except it is for single barrels. I can't imagine McGurk not putting his name on it.
This is the same style only said to be a Wayne. There was a mention of both Wayne and McGurk selling the same manifold. Maybe there is no name because they both used it. I have a Clifford with no name that was cast by Offenhauser because I bought it in the middle of a design change or at least that is what Clifford told me.
Or a Lee. This one looks like someone turned the log around. I didn't find a 2 bbl manifold.
This all came from this thread on the HAMB.
LINK 
