Originally Posted by Iggy

Maybe.
I had considered switching to a cross-over when an OSO memebr stated the Alpha pump wasn't strong enough to handel it. A Bravo pump would be needed. Then somebody else said it will work. I'm not sure anymore.
The circulator pump on the engine is just that, a circulator pump. It dosen't pull any water up from the Alpha drive.
Alpha equiped SBC's use a different t-stat housing. It has two check valves in the hoses leading to the exhaust manifolds. These valves restrict the water flow to the manifolds at ide and increases the flow through the block to prevent overheating at idle.