1998 SCR3000 Repower

[Viper]

I have a 1998 3000SCR with Twin 5.0L Bravo II. 2-Barrel Carbureted.

I have been told I have dead Holes in both engines. I still need to confirm this myself and do a leak-down test to see if it is rings or Heads.

But a suggestion was to do Mercruiser Drop-ins. And upgrade.

Has anyone done this, wondering if the newer 5.7L (350) or 383CUI MPI engines will still be a drop-in. Since mine is not a Vortec, and not Fuel injected.

Would I need to re-gear drives or change prop pitch?