I have an extra 8BA laying around, and I have a recurring fantasy about building a sweet little mahogany runabout, and putting a full-dress flattie in it. I know they had marine conversions in the old days, but I've never had any luck finding parts. Does anyone make a marine exhaust manifold anymore? I'm a machinist and welder; I could probably make my own manifolds, but what about spark-proof ignition, generator, and starter? You don't want automotive electrical stuff in the bilge of a boat; gasoline fumes can accumulate there, and a spark will give you a whole new perspective on 0-60! Also, I'd have to find or adapt a marine tranny, too.
i had a flat head ford six marine around 1968 that was in a old woodie boat . i think if you do a google search for old marine engines you'l come up with a few companies i know for sure there is some one in li ny doing redoing the old flat 4 marines also look up osco they make a lot of replacement manifolds for old motors. good luck it would be a fine marriage