Usually, marine used better parts, forged internals, etc. 327 all had forged cranks. The marine engine will likely require cam change, etc. to match desired rpm range. As for reversed rotation, that is possible, the ones I've seen that were reversed were twin engine application, one is standard, one reversed... I'm sure there are exceptions. Freezing and overheating are prominent marine engine failure issues. Hard to beat a 327.
