What is your “D” dimensions?
Im guessing you have a 162 blower.
The 177 have a 6 bolt pattern and are based of of the Weiand blower company.
The B&M’s were offered in 144 and 162 with the B&M cast manifold, the 174 was offered by DLI with a modified Offenhauser manifold.
GLWS
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