SAE doc #700080
The original paper regarding the 351C 4V, presented by F. Miller and J. Van Deun of the Ford Motor Company to the SAE Congress convened in Detroit Michigan January 12-16, 1970.
Here is an excerpt from page 20 of this document. I believe it verifies the expectation of Ford engineers was for all coolant to be blocked from recirculation and to flow through the radiator.