I just picked up a 20' sutphen jet boat with no power ,boat is rigged for a 454 and came with everything to install the motor. Front and rear mounts ,exhaust logs and driveshaft.i have a friend who has a fresh drop in mercruiser 454 magnum.will I have any issues making this motor work in the boat ? Will all the parts fit on this engine ? There was a gen4 big block in the boat originally and the motor I'm looking to buy is also a gen4. Thanks happy new year!