The original Twin Cam fuel pump has the rectangular output end (vs round end on the pushrod cars). Output capacity is 12.5 GPH vs 10 GPH for the pushrod cars. Photo above has incorrect banjo fittings. They should have male threaded pipe connector as shown below. Also notice words on the casting, "Top, Inlet, Outlet".

Photo compliments of Mark Hester (back in London, England by now).