That whole front assembly should just swap right over to another first gen or second gen small block; just keep good notes and take a lot of pictures for reference as you dis-assemble it. The right hand cam-left hand cam thing: it seems to me that in multi engine applications, one engine turns one direction and the other goes opposite, something about balancing the thrust from the props so your boat doesn't try to run in circles all the time. There are a couple of guys here who are former marine mechanics, maybe they will chime in here. The only thing I ever had to do with boat engines was getting them out of the hull so we could get to the rebuild part, and then dropping them back in right where they came from, and they were always single engine boats. I have reached the limit of my experience here.

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