Only the cam,
oil pump and starter really differ. The crank will need to be balanced neutral, just as it would in conventional rotation. The oiling is the same. Remember, it still goes through the same passages. The pump itself, runs in reverse at the shaft, but the design of the pump body flows the
oil as normal rotation would. I've heard that some pumps have an extra gear to change the pump gear rotation. Don't know about that for sure.
If using a marine 427, don't make the mistake of not changing the
oil pump to conventional. The cam is a given for change as is the starter. Any good auto electric shop can change the polarity of the starter for you. Probably just as cheap to buy a new on though.
Last note; look carefully at the condition of the block and heads. Corrosion can be a big item if the engine was used in salt water without a closed, fresh water cooling system.
Al