I have a line on a good, low mileage 460 complete engine, is there anything special that needs to be done to stuff it in the boat?

Thanks

Skip

Guess I'll ad, depends on what you want your boat to do. Like lilrick said, these motors are a higher rpm/high load type motor (typically)
So if high speed, more hp is your goal,   cam, head work, lifters, valves, roller rockers, pushrods. In your case, botom end (crank) will do stock well up and over 500hp,
but you might want to change pistons and rods too. Plus to match it all...  intake, carb, headers...   the list grows...  just ask anyone here how much they have spent to reach 60-80 mph    
typical Marine motor is overbuilt compaired to car/truck    but depending on what you want...  simple changes can make it work!
Performance costs 

Rebel

You can put your engine in a boat , it just won't live as long and won't push the boat very fast.

You need the pistons looser in the bore, much like a motor set up for nitrous.
The ring end gaps need to be about 2x the clearance of a normal passenger car.

This all has to do with the temps that build up inside the chamber at high load for extended periods.

The other thing is the freeze plugs, they need to be brass so they don't corrode in salt. If you are riverbound only, you may be able to get by without, however, the engine is still lacking antifreeze so there still may be corrosion issues (but it will take much longer to show up).