donzi hornet engine change 454 to 496 or 502 mpi

[CCTBJ]

Considering changing my current 454 carb motor to newer 496 or 502 mpi. Just curious of any issues I might encounter. Boat has TRS drive and I plan to keep that. Just don't know about motor mount location,flywheels the same,pilot etc.. Any help greatly appreciated.
Charlie

[gcarter]

The engines are physuically the same size, the difference will be in the fuel system.
Lots of extra parts there.

[Pismo]

502 will be closest. Mounts should line up, bell housing is correct, same flywheel. Same everything except the fuel delivery will be different if your 454 is Gen 4, might be the same if it is newer.