Did you buy a flat tappet or roller lifter engine? If flat tappet you will need to do a break in run on first start up. You can do this on the ground out of the boat which I'd suggest. That way if you have any problems you won't have already installed the engine.
You will need to set up the distributor and carburetor, and you will need a side tank with fuel to the pump.
You can make a square ground cradle with some 2 x 8's and 2 x 10's, The rear mounts are higher than the fronts so you use the wider board there. Keeps the motor level.
Fill it with break in oil, and run it for 30 minutes at 1800 to 2500 rpm. No idling, just run it at those rpms so there is plenty of oil to your new cam. This is the one time to rev a cold motor.
Then change the filter and oil, put in something with zinc or zddp. I used Joe Gibbs Driven break in oil on my cam and then I used Quaker State Defy (it is manfactured with zinc in the blend) last summer. Only problem with the Defy is it's the grade you'd use in a car or truck, 10w30. Mercruiser says to use something 40 weight during summer. If you want to follow the program and still care for the flat tappet cam you could do 40 weight and get a some zinc additive.
I'm really excited for you, your boat will rip with a 5.7!
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